Those who have been active in the Bitcoin and cryptocurrency space for a while are probably aware of Primecoin (XPM) – a cryptocurrency that contributes to scientific and mathematical research by searching for primes. There has been a lot of discussion about how wasteful Bitcoin mining is in terms of energy usage and resources and Primecoin’s innovative proof-of-work algorithm is viewed by some in the cryptocurrency community as a potential way of turn mining into something that can be more useful for society. But Primecoin isn’t the only altcoin with mathematical research in mind out there – there’s Riecoin (RIC) too.

While Primecoin and Riecoin have their own independent development teams and communities, saying that Riecoin is Primecoin’s little brother seems like quite an accurate description. Both were developed by pseudonymous developers: Primecoin was launched in 2013 by Sunny King who would later go on to develop the first proof-of-stake coin in the form of Peercoin while Riecoin was launched in 2014 by a developer who went by the name of gatra on the BitcoinTalk forum. Perhaps as a nod to Satoshi Nakamoto, both Sunny King and gatra also stepped away from development of their coins after a few years and handed over the reins to their respective communities.

Both coins are CPU mineable (although Primecoin can be mined more efficiently with GPUs now) which is a bit of a rarity in today’s ASIC dominated world. While SHA-256-based coins like Bitcoin and Namecoin and scrypt-based coins like Litecoin and Dogecoin have been dominated by ASICs for a several years now, coins like Primecoin and Riecoin show that mining with regular home computers is still feasible in this day and age.

In terms of differences, Primecoin has 1 minute blocks, no maximum cap on coins, continuous difficulty adjustment, block rewards that are determined by the current difficulty, and a centralized checkpointing system. Riecoin on the other hand has 2.5 minute blocks, a maximum cap of 84 million coins, difficulty retargeting every 12 hours, and block rewards of 50 coins – halving every 4 years.

Both coins look for chains of prime numbers but Primecoin looks for Cunningham and bi-twin chains while Riecoin looks for chains of primes with minimum possible distances between each other. Primecoin also uses a combination of the Euler-Lagrange-Lifchitz and Fermat tests to prove primality (a faster but less accurate method) while Riecoin uses the Miller-Rabin test to test for primality (a slower but more accurate method).

Market cap-wise, Primecoin is certainly in the lead. As of July 8, 2024, Primecoin has a market cap of nearly $1.4 million while Riecoin’s is only $500,000. Both coins had fair launches with no signs of premines, instamines, ninjamines, and so on that plague the cryptocurrency community (I’m looking at you Bytecoin). From the Riecoin announcement thread:

“Fair launch:

Since this is a new PoW, it is very hard to define a starting difficulty that avoids instamining. To overcome this and contribute to a fair launch, the first 576 blocks will have no reward and the next 576 will linearly increase and reach the full reward at block 1,152, after 4 difficulty adjustments were performed. Besides avoiding instamining, this should allow time for those who want to compile their own clients. Expect the starting difficulty to be hard.

Source code will be provided a few days before launch, but the PoW functions will be replaced by stubs. The idea is that everyone would be able to examine the code and confirm that there’s nothing strange and it is indeed pretty similar to Bitcoin’s. Everyone would be able to compile it, see if they have the correct dependencies, etc. but it won’t run. At launch time, when the final code is released, everyone could easily check that the only thing that changed is the PoW code, so you’d only have to check the diff of a few lines of code and recompile.”

If you are interested in what Riecoin has to offer then I encourage you to visit the official website. It has all of the information you need to download, install, and run the software and guides to set up mining either by yourself or in a pool. There is also a handy link to download the entire blockchain bootstrap so that you don’t have to spend hours to days waiting for the client to sync up with the network.

Alternatively, if mining isn’t your cup of tea then you can head over to FreiExchange and buy them directly.

So far, I’ve been mining on a mid-range gaming laptop with an Intel Core i7-8750H for the last three hours and it takes little less than a day on average to mine a block. That being said, I don’t recommend mining on laptops for extended periods since their thermal designs aren’t as good as desktops.