Block #456,771

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/23/2014, 11:05:01 AM · Difficulty 10.4175 · 6,346,641 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
5b2bc9189f0c096adcc66f8c806829f61aeac1e851bed9214a1cb65c3ba2b022

Height

#456,771

Difficulty

10.417537

Transactions

9

Size

2.83 KB

Version

2

Bits

0a6ae3b7

Nonce

78,036

Timestamp

3/23/2014, 11:05:01 AM

Confirmations

6,346,641

Merkle Root

255cbd03f13464e64488d0730520274f1e1184b78efdfb989499d4d11548b6a4
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.

9.516 × 10⁹⁶(97-digit number)
95160635357202680423…16899167308543052799
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
9.516 × 10⁹⁶(97-digit number)
95160635357202680423…16899167308543052799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.903 × 10⁹⁷(98-digit number)
19032127071440536084…33798334617086105599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.806 × 10⁹⁷(98-digit number)
38064254142881072169…67596669234172211199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.612 × 10⁹⁷(98-digit number)
76128508285762144338…35193338468344422399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.522 × 10⁹⁸(99-digit number)
15225701657152428867…70386676936688844799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.045 × 10⁹⁸(99-digit number)
30451403314304857735…40773353873377689599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.090 × 10⁹⁸(99-digit number)
60902806628609715470…81546707746755379199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.218 × 10⁹⁹(100-digit number)
12180561325721943094…63093415493510758399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.436 × 10⁹⁹(100-digit number)
24361122651443886188…26186830987021516799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.872 × 10⁹⁹(100-digit number)
48722245302887772376…52373661974043033599
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:57,671,326 XPM·at block #6,803,411 · updates every 60s
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