Block #226,032

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 10/24/2013, 10:42:12 PM · Difficulty 9.9360 · 6,565,884 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b3d51d131e102212d394562da0e854d3779cb431b5928aec8093cd29ed398401

Height

#226,032

Difficulty

9.936033

Transactions

5

Size

2.03 KB

Version

2

Bits

09ef9fd8

Nonce

588,295

Timestamp

10/24/2013, 10:42:12 PM

Confirmations

6,565,884

Merkle Root

5fc66f1abeb2ff316210b601d148ce317ce362338cf198bd8bd83b82a8ffbe69
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.

3.098 × 10⁹³(94-digit number)
30988247613966500871…28267974168976538239
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
3.098 × 10⁹³(94-digit number)
30988247613966500871…28267974168976538239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.197 × 10⁹³(94-digit number)
61976495227933001743…56535948337953076479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.239 × 10⁹⁴(95-digit number)
12395299045586600348…13071896675906152959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.479 × 10⁹⁴(95-digit number)
24790598091173200697…26143793351812305919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.958 × 10⁹⁴(95-digit number)
49581196182346401394…52287586703624611839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.916 × 10⁹⁴(95-digit number)
99162392364692802788…04575173407249223679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.983 × 10⁹⁵(96-digit number)
19832478472938560557…09150346814498447359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.966 × 10⁹⁵(96-digit number)
39664956945877121115…18300693628996894719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.932 × 10⁹⁵(96-digit number)
79329913891754242231…36601387257993789439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.586 × 10⁹⁶(97-digit number)
15865982778350848446…73202774515987578879
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:57,579,281 XPM·at block #6,791,915 · updates every 60s
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