Block #327,436

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/24/2013, 1:16:53 PM · Difficulty 10.1780 · 6,468,284 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b8ec9baeb87b248f28b988ab3d839a4c06fcbc91aba9b0533334c24cb52e5f52

Height

#327,436

Difficulty

10.178023

Transactions

6

Size

1.30 KB

Version

2

Bits

0a2d92e6

Nonce

69,883

Timestamp

12/24/2013, 1:16:53 PM

Confirmations

6,468,284

Merkle Root

e1fcf52b70258805550adc147a6d55d945199072d492c001860d2b53b7924768
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.

4.478 × 10⁹⁷(98-digit number)
44787054583873654960…92889007110767226879
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
4.478 × 10⁹⁷(98-digit number)
44787054583873654960…92889007110767226879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.957 × 10⁹⁷(98-digit number)
89574109167747309920…85778014221534453759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.791 × 10⁹⁸(99-digit number)
17914821833549461984…71556028443068907519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.582 × 10⁹⁸(99-digit number)
35829643667098923968…43112056886137815039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.165 × 10⁹⁸(99-digit number)
71659287334197847936…86224113772275630079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.433 × 10⁹⁹(100-digit number)
14331857466839569587…72448227544551260159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.866 × 10⁹⁹(100-digit number)
28663714933679139174…44896455089102520319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.732 × 10⁹⁹(100-digit number)
57327429867358278349…89792910178205040639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.146 × 10¹⁰⁰(101-digit number)
11465485973471655669…79585820356410081279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.293 × 10¹⁰⁰(101-digit number)
22930971946943311339…59171640712820162559
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:57,609,835 XPM·at block #6,795,719 · updates every 60s
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