Block #362,645

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/16/2014, 8:40:02 PM · Difficulty 10.4158 · 6,443,259 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
75a951f1d652e22b9dbe9cc639b004356e62e534b629c2eb2009a6c2b987f2df

Height

#362,645

Difficulty

10.415769

Transactions

6

Size

1.64 KB

Version

2

Bits

0a6a6fd8

Nonce

117,443,773

Timestamp

1/16/2014, 8:40:02 PM

Confirmations

6,443,259

Merkle Root

f26c1da16c56d4c6fbe55792a3aafa37c0aa47ffad1e76032fddbc29c52d3bc3
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.

2.557 × 10⁹⁵(96-digit number)
25579156838145823492…57471639925738094239
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
2.557 × 10⁹⁵(96-digit number)
25579156838145823492…57471639925738094239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.115 × 10⁹⁵(96-digit number)
51158313676291646984…14943279851476188479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.023 × 10⁹⁶(97-digit number)
10231662735258329396…29886559702952376959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.046 × 10⁹⁶(97-digit number)
20463325470516658793…59773119405904753919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.092 × 10⁹⁶(97-digit number)
40926650941033317587…19546238811809507839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
8.185 × 10⁹⁶(97-digit number)
81853301882066635175…39092477623619015679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.637 × 10⁹⁷(98-digit number)
16370660376413327035…78184955247238031359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.274 × 10⁹⁷(98-digit number)
32741320752826654070…56369910494476062719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.548 × 10⁹⁷(98-digit number)
65482641505653308140…12739820988952125439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.309 × 10⁹⁸(99-digit number)
13096528301130661628…25479641977904250879
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:57,691,320 XPM·at block #6,805,903 · updates every 60s
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