Block #463,740

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/28/2014, 8:25:56 AM · Difficulty 10.4135 · 6,341,972 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4cd62d5148a5b24396b68737dd14e9fe3f393f332e12a7fb4d0ca2494d593573

Height

#463,740

Difficulty

10.413493

Transactions

7

Size

1.82 KB

Version

2

Bits

0a69daa5

Nonce

98,598

Timestamp

3/28/2014, 8:25:56 AM

Confirmations

6,341,972

Merkle Root

be480e471c00a244a918b63eb500f5d9a97c9a948dba1e528445a00262cbdd6b
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.

4.863 × 10⁹³(94-digit number)
48633392307748899590…59232857829111911999
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
4.863 × 10⁹³(94-digit number)
48633392307748899590…59232857829111911999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.726 × 10⁹³(94-digit number)
97266784615497799181…18465715658223823999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.945 × 10⁹⁴(95-digit number)
19453356923099559836…36931431316447647999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.890 × 10⁹⁴(95-digit number)
38906713846199119672…73862862632895295999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.781 × 10⁹⁴(95-digit number)
77813427692398239345…47725725265790591999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.556 × 10⁹⁵(96-digit number)
15562685538479647869…95451450531581183999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.112 × 10⁹⁵(96-digit number)
31125371076959295738…90902901063162367999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.225 × 10⁹⁵(96-digit number)
62250742153918591476…81805802126324735999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.245 × 10⁹⁶(97-digit number)
12450148430783718295…63611604252649471999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.490 × 10⁹⁶(97-digit number)
24900296861567436590…27223208505298943999
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:57,689,779 XPM·at block #6,805,711 · updates every 60s
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