Block #789,557

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 10/30/2014, 2:58:59 PM · Difficulty 10.9741 · 6,012,929 confirmations

1CC
Cunningham Chain of the First Kind

A sequence where each prime is double the previous prime plus one.

Block Header
Block Hash
9369f64992bc5eee84564255504f773202d3361d6642c4baca796f1d05a6125f

Height

#789,557

Difficulty

10.974060

Transactions

3

Size

955 B

Version

2

Bits

0af95c01

Nonce

154,028,114

Timestamp

10/30/2014, 2:58:59 PM

Confirmations

6,012,929

Merkle Root

1dc641465367c6fab428b4b3410b0a5868359e1d2530a8989ec5072c2a1b8fa9
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.

1.569 × 10⁹⁶(97-digit number)
15693737287419795119…52982102215202531839
Discovered Prime Numbers
p_k = 2^k × origin − 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

1
origin − 1
1.569 × 10⁹⁶(97-digit number)
15693737287419795119…52982102215202531839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.138 × 10⁹⁶(97-digit number)
31387474574839590238…05964204430405063679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
6.277 × 10⁹⁶(97-digit number)
62774949149679180476…11928408860810127359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.255 × 10⁹⁷(98-digit number)
12554989829935836095…23856817721620254719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.510 × 10⁹⁷(98-digit number)
25109979659871672190…47713635443240509439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.021 × 10⁹⁷(98-digit number)
50219959319743344381…95427270886481018879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.004 × 10⁹⁸(99-digit number)
10043991863948668876…90854541772962037759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.008 × 10⁹⁸(99-digit number)
20087983727897337752…81709083545924075519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.017 × 10⁹⁸(99-digit number)
40175967455794675505…63418167091848151039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
8.035 × 10⁹⁸(99-digit number)
80351934911589351010…26836334183696302079
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 consecutive prime numbers forming a Cunningham Chain of the First Kind. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

★★☆☆☆
Rarity
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,663,901 XPM·at block #6,802,485 · updates every 60s
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