Block #459,222

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 3/25/2014, 4:13:13 AM · Difficulty 10.4172 · 6,340,131 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
1be95f77432029e220623d59dea0c07481f40ba3b0d420f2fb7dd228a87b2cde

Height

#459,222

Difficulty

10.417174

Transactions

22

Size

7.60 KB

Version

2

Bits

0a6acbe8

Nonce

7,750

Timestamp

3/25/2014, 4:13:13 AM

Confirmations

6,340,131

Merkle Root

d0963b21a4d6c319718907f4118292a096fe70cb1baebd165870d7ef54712b64
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.

1.485 × 10⁹⁷(98-digit number)
14851441767593484520…38458182394134221171
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
1.485 × 10⁹⁷(98-digit number)
14851441767593484520…38458182394134221171
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.970 × 10⁹⁷(98-digit number)
29702883535186969041…76916364788268442341
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
5.940 × 10⁹⁷(98-digit number)
59405767070373938083…53832729576536884681
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.188 × 10⁹⁸(99-digit number)
11881153414074787616…07665459153073769361
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.376 × 10⁹⁸(99-digit number)
23762306828149575233…15330918306147538721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
4.752 × 10⁹⁸(99-digit number)
47524613656299150466…30661836612295077441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
9.504 × 10⁹⁸(99-digit number)
95049227312598300933…61323673224590154881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.900 × 10⁹⁹(100-digit number)
19009845462519660186…22647346449180309761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
3.801 × 10⁹⁹(100-digit number)
38019690925039320373…45294692898360619521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
7.603 × 10⁹⁹(100-digit number)
76039381850078640746…90589385796721239041
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 Second 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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,638,877 XPM·at block #6,799,352 · updates every 60s
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