Block #504,771

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/21/2014, 11:58:04 PM · Difficulty 10.8103 · 6,291,312 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
6b833e4e276b63ea7006afe404e0ca3786b28b175b9e919cae805d31ec98874b

Height

#504,771

Difficulty

10.810294

Transactions

10

Size

3.33 KB

Version

2

Bits

0acf6f72

Nonce

45,529

Timestamp

4/21/2014, 11:58:04 PM

Confirmations

6,291,312

Merkle Root

e4e6d399b9168c4d5efdc4cae32e161c8cb002ac16f7eda8e729cc733f062013
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.

1.095 × 10¹⁰¹(102-digit number)
10954653233769106278…50810980408603463999
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
1.095 × 10¹⁰¹(102-digit number)
10954653233769106278…50810980408603463999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.190 × 10¹⁰¹(102-digit number)
21909306467538212557…01621960817206927999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.381 × 10¹⁰¹(102-digit number)
43818612935076425115…03243921634413855999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.763 × 10¹⁰¹(102-digit number)
87637225870152850231…06487843268827711999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.752 × 10¹⁰²(103-digit number)
17527445174030570046…12975686537655423999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.505 × 10¹⁰²(103-digit number)
35054890348061140092…25951373075310847999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.010 × 10¹⁰²(103-digit number)
70109780696122280185…51902746150621695999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.402 × 10¹⁰³(104-digit number)
14021956139224456037…03805492301243391999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.804 × 10¹⁰³(104-digit number)
28043912278448912074…07610984602486783999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.608 × 10¹⁰³(104-digit number)
56087824556897824148…15221969204973567999
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:57,612,661 XPM·at block #6,796,082 · updates every 60s
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