Block #441,494

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/13/2014, 4:39:34 AM · Difficulty 10.3487 · 6,363,679 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f0553f3fa73feb3b0ed82fcf6449351cc4cbd58aa75b282ca5fae25ecb45df55

Height

#441,494

Difficulty

10.348705

Transactions

4

Size

1.65 KB

Version

2

Bits

0a5944b7

Nonce

113,710

Timestamp

3/13/2014, 4:39:34 AM

Confirmations

6,363,679

Merkle Root

917c409209fc10a66346bbbc989e62e5341b8796c9571ba73f87911b85b1ffc4
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.

7.645 × 10⁹²(93-digit number)
76456970949014024628…82623539022920540159
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
7.645 × 10⁹²(93-digit number)
76456970949014024628…82623539022920540159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.529 × 10⁹³(94-digit number)
15291394189802804925…65247078045841080319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.058 × 10⁹³(94-digit number)
30582788379605609851…30494156091682160639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.116 × 10⁹³(94-digit number)
61165576759211219702…60988312183364321279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.223 × 10⁹⁴(95-digit number)
12233115351842243940…21976624366728642559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.446 × 10⁹⁴(95-digit number)
24466230703684487881…43953248733457285119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.893 × 10⁹⁴(95-digit number)
48932461407368975762…87906497466914570239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.786 × 10⁹⁴(95-digit number)
97864922814737951524…75812994933829140479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.957 × 10⁹⁵(96-digit number)
19572984562947590304…51625989867658280959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.914 × 10⁹⁵(96-digit number)
39145969125895180609…03251979735316561919
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:57,685,452 XPM·at block #6,805,172 · updates every 60s
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