Block #327,137

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/24/2013, 8:14:31 AM · Difficulty 10.1784 · 6,468,806 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
342b5459e176df9a8c7698c0c9f352ca8bf7c62a5080b698735f180486c3a3ea

Height

#327,137

Difficulty

10.178369

Transactions

27

Size

7.28 KB

Version

2

Bits

0a2da998

Nonce

61,749

Timestamp

12/24/2013, 8:14:31 AM

Confirmations

6,468,806

Merkle Root

046a5ce318a1ba56e0d11cd54aa082bfb10a4ef77ad3fe34c5e8e17c3a63e19f
Transactions (27)
1 in → 1 out9.9344 XPM110 B
1 in → 1 out10.0500 XPM157 B
1 in → 1 out10.0500 XPM158 B
1 in → 1 out10.0200 XPM157 B
3 in → 1 out29.6800 XPM387 B
2 in → 1 out19.6500 XPM271 B
3 in → 1 out29.3100 XPM385 B
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.

2.295 × 10¹⁰¹(102-digit number)
22950682087773715681…58444333804048012799
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
2.295 × 10¹⁰¹(102-digit number)
22950682087773715681…58444333804048012799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.590 × 10¹⁰¹(102-digit number)
45901364175547431362…16888667608096025599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.180 × 10¹⁰¹(102-digit number)
91802728351094862725…33777335216192051199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.836 × 10¹⁰²(103-digit number)
18360545670218972545…67554670432384102399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.672 × 10¹⁰²(103-digit number)
36721091340437945090…35109340864768204799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.344 × 10¹⁰²(103-digit number)
73442182680875890180…70218681729536409599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.468 × 10¹⁰³(104-digit number)
14688436536175178036…40437363459072819199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.937 × 10¹⁰³(104-digit number)
29376873072350356072…80874726918145638399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.875 × 10¹⁰³(104-digit number)
58753746144700712144…61749453836291276799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.175 × 10¹⁰⁴(105-digit number)
11750749228940142428…23498907672582553599
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:57,611,632 XPM·at block #6,795,942 · updates every 60s
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