Block #562,171

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 5/25/2014, 10:56:09 PM · Difficulty 10.9660 · 6,241,387 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b440c6b28ad15cbb0ddfd294245b2a993f0ab676f887db6fde14303a8d1f7ee4

Height

#562,171

Difficulty

10.965967

Transactions

4

Size

1.00 KB

Version

2

Bits

0af749a2

Nonce

84,328,155

Timestamp

5/25/2014, 10:56:09 PM

Confirmations

6,241,387

Merkle Root

37f28fe27af14fb4b4b90ba45b0109dcf6600a9a1e5401e8d9622047a62b1e5f
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.

3.791 × 10⁹⁷(98-digit number)
37913916332235862946…54523601975517550079
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
3.791 × 10⁹⁷(98-digit number)
37913916332235862946…54523601975517550079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.582 × 10⁹⁷(98-digit number)
75827832664471725893…09047203951035100159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.516 × 10⁹⁸(99-digit number)
15165566532894345178…18094407902070200319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.033 × 10⁹⁸(99-digit number)
30331133065788690357…36188815804140400639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.066 × 10⁹⁸(99-digit number)
60662266131577380714…72377631608280801279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.213 × 10⁹⁹(100-digit number)
12132453226315476142…44755263216561602559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.426 × 10⁹⁹(100-digit number)
24264906452630952285…89510526433123205119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.852 × 10⁹⁹(100-digit number)
48529812905261904571…79021052866246410239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.705 × 10⁹⁹(100-digit number)
97059625810523809143…58042105732492820479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.941 × 10¹⁰⁰(101-digit number)
19411925162104761828…16084211464985640959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
3.882 × 10¹⁰⁰(101-digit number)
38823850324209523657…32168422929971281919
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,672,495 XPM·at block #6,803,557 · updates every 60s
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