Block #447,530

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/17/2014, 8:32:47 AM · Difficulty 10.3570 · 6,356,769 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
09c51760720c9b9195d42717f84b44e4413e7aeb05d81a802933b35250511f88

Height

#447,530

Difficulty

10.357025

Transactions

2

Size

1.17 KB

Version

2

Bits

0a5b6604

Nonce

202,713

Timestamp

3/17/2014, 8:32:47 AM

Confirmations

6,356,769

Merkle Root

e93fcbf4f02b40aef64a107332963e6af6767ad34a4aa31b5c0253ee1a704508
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.

9.698 × 10⁹⁴(95-digit number)
96984427079750627968…80721708253327176799
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
9.698 × 10⁹⁴(95-digit number)
96984427079750627968…80721708253327176799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.939 × 10⁹⁵(96-digit number)
19396885415950125593…61443416506654353599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.879 × 10⁹⁵(96-digit number)
38793770831900251187…22886833013308707199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.758 × 10⁹⁵(96-digit number)
77587541663800502374…45773666026617414399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.551 × 10⁹⁶(97-digit number)
15517508332760100474…91547332053234828799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.103 × 10⁹⁶(97-digit number)
31035016665520200949…83094664106469657599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.207 × 10⁹⁶(97-digit number)
62070033331040401899…66189328212939315199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.241 × 10⁹⁷(98-digit number)
12414006666208080379…32378656425878630399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.482 × 10⁹⁷(98-digit number)
24828013332416160759…64757312851757260799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.965 × 10⁹⁷(98-digit number)
49656026664832321519…29514625703514521599
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:57,678,451 XPM·at block #6,804,298 · updates every 60s
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