Block #375,057

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/25/2014, 11:26:34 AM · Difficulty 10.4209 · 6,423,863 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
d1ed19fda8535151e97aaf4e7728ed618f3d15b913979630ab1d0302a9e52421

Height

#375,057

Difficulty

10.420922

Transactions

2

Size

1.62 KB

Version

2

Bits

0a6bc191

Nonce

351,341

Timestamp

1/25/2014, 11:26:34 AM

Confirmations

6,423,863

Merkle Root

6fab92ee9b83503b5a1163c2f06eb26fea45d9f1b1074c6c613ead29740ca37f
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.

7.164 × 10⁹³(94-digit number)
71648986655525176800…25612737081851401559
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
7.164 × 10⁹³(94-digit number)
71648986655525176800…25612737081851401559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.432 × 10⁹⁴(95-digit number)
14329797331105035360…51225474163702803119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.865 × 10⁹⁴(95-digit number)
28659594662210070720…02450948327405606239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.731 × 10⁹⁴(95-digit number)
57319189324420141440…04901896654811212479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.146 × 10⁹⁵(96-digit number)
11463837864884028288…09803793309622424959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.292 × 10⁹⁵(96-digit number)
22927675729768056576…19607586619244849919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.585 × 10⁹⁵(96-digit number)
45855351459536113152…39215173238489699839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.171 × 10⁹⁵(96-digit number)
91710702919072226305…78430346476979399679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.834 × 10⁹⁶(97-digit number)
18342140583814445261…56860692953958799359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.668 × 10⁹⁶(97-digit number)
36684281167628890522…13721385907917598719
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:57,635,392 XPM·at block #6,798,919 · updates every 60s
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