Block #79,789

2CC09.505165

Discovered 7/23/2013, 5:47:11 PM · Difficulty 9.2438 · 6,715,354 confirmations

Block Header

Block Hash

2c7d100fd08a2738936ba241db4bcd8ecacc1e8ca018b1f5c7842031a16b706d

View on Chainz ↗

Height

#79,789

Difficulty

9.243791

Transactions

Size

651 B

Version

Bits

093e691a

Nonce

189

Timestamp

7/23/2013, 5:47:11 PM

Confirmations

6,715,354

Mined by

⛏️ P2SHAXcftiEWBNoczD7B3BxYGhgwrtzmZznXAg

Merkle Root

2211870dd60a616d24474abbaa410828462738ab2ffab9a3372eafecff576a3b

Transactions (3)

Coinbase1eb40b1a4c569d…4c11d974e25485

1 in → 1 out11.7100 XPM110 B

AXcftiEW…zmZznXAg

7a3bc4c4a693c9…46672e3cf10766

1 in → 2 out104.9900 XPM227 B

ASYoSewf…BPCS2hAd AKKb38vw…nN1DKpfW

855c871bf095f0…e24ef35944cfbf

1 in → 2 out3.7264 XPM225 B

AFtseNXx…3yZq1Yq2 AajQ82bx…DWka2Fkf

Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

2.905 × 10⁹¹(92-digit number)

29059098230044607144…97739403581148876920

How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)

Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the 2CC09.505165 formula:

Cross-reference on Chainz Explorer