Block #471,417

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/2/2014, 1:58:00 PM · Difficulty 10.4347 · 6,332,365 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
72d868d967483c17005aa17420df8d9527a689edbc03e1601ed86edbdfaa2124

Height

#471,417

Difficulty

10.434746

Transactions

6

Size

1.35 KB

Version

2

Bits

0a6f4b86

Nonce

6,591

Timestamp

4/2/2014, 1:58:00 PM

Confirmations

6,332,365

Merkle Root

313a31ba9a737e9363e2b710a9ae198f72c2b3e74637419da92ac2d793c543b8
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.

3.256 × 10⁹³(94-digit number)
32566202079095057769…36394967742941248739
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
3.256 × 10⁹³(94-digit number)
32566202079095057769…36394967742941248739
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.513 × 10⁹³(94-digit number)
65132404158190115539…72789935485882497479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.302 × 10⁹⁴(95-digit number)
13026480831638023107…45579870971764994959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.605 × 10⁹⁴(95-digit number)
26052961663276046215…91159741943529989919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.210 × 10⁹⁴(95-digit number)
52105923326552092431…82319483887059979839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.042 × 10⁹⁵(96-digit number)
10421184665310418486…64638967774119959679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.084 × 10⁹⁵(96-digit number)
20842369330620836972…29277935548239919359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.168 × 10⁹⁵(96-digit number)
41684738661241673945…58555871096479838719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.336 × 10⁹⁵(96-digit number)
83369477322483347890…17111742192959677439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.667 × 10⁹⁶(97-digit number)
16673895464496669578…34223484385919354879
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:57,674,296 XPM·at block #6,803,781 · updates every 60s
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