Block #445,972

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/16/2014, 6:16:04 AM · Difficulty 10.3587 · 6,350,219 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e093a48c7171e7e16b0907fabb3729a3e3614cb7b6b10a7c074909f21801b132

Height

#445,972

Difficulty

10.358738

Transactions

2

Size

1.92 KB

Version

2

Bits

0a5bd63b

Nonce

77,102

Timestamp

3/16/2014, 6:16:04 AM

Confirmations

6,350,219

Merkle Root

8661d42b05c36cdbb57cca1cd811772b8dffd24149ee1f31a3b6840b48295a4c
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.

3.938 × 10⁹⁰(91-digit number)
39382237892614654217…48069185698999807999
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
3.938 × 10⁹⁰(91-digit number)
39382237892614654217…48069185698999807999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.876 × 10⁹⁰(91-digit number)
78764475785229308435…96138371397999615999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.575 × 10⁹¹(92-digit number)
15752895157045861687…92276742795999231999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.150 × 10⁹¹(92-digit number)
31505790314091723374…84553485591998463999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.301 × 10⁹¹(92-digit number)
63011580628183446748…69106971183996927999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.260 × 10⁹²(93-digit number)
12602316125636689349…38213942367993855999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.520 × 10⁹²(93-digit number)
25204632251273378699…76427884735987711999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.040 × 10⁹²(93-digit number)
50409264502546757398…52855769471975423999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.008 × 10⁹³(94-digit number)
10081852900509351479…05711538943950847999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.016 × 10⁹³(94-digit number)
20163705801018702959…11423077887901695999
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:57,613,527 XPM·at block #6,796,190 · updates every 60s
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