Block #360,074

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/15/2014, 5:29:35 AM · Difficulty 10.3890 · 6,443,236 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
fb8a84dff80995e1fa414815d31222d643160d791e8bc3c9fef72b81f23125ae

Height

#360,074

Difficulty

10.389033

Transactions

11

Size

17.11 KB

Version

2

Bits

0a6397a8

Nonce

62,901

Timestamp

1/15/2014, 5:29:35 AM

Confirmations

6,443,236

Merkle Root

15ad022bd8b0a02cd0c1edf0d61d20acab24cae0c599ed2c3973e8da8e0a7ded
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.

4.953 × 10¹⁰¹(102-digit number)
49536911852128546575…66448349334052034559
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
4.953 × 10¹⁰¹(102-digit number)
49536911852128546575…66448349334052034559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.907 × 10¹⁰¹(102-digit number)
99073823704257093150…32896698668104069119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.981 × 10¹⁰²(103-digit number)
19814764740851418630…65793397336208138239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.962 × 10¹⁰²(103-digit number)
39629529481702837260…31586794672416276479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.925 × 10¹⁰²(103-digit number)
79259058963405674520…63173589344832552959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.585 × 10¹⁰³(104-digit number)
15851811792681134904…26347178689665105919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.170 × 10¹⁰³(104-digit number)
31703623585362269808…52694357379330211839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.340 × 10¹⁰³(104-digit number)
63407247170724539616…05388714758660423679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.268 × 10¹⁰⁴(105-digit number)
12681449434144907923…10777429517320847359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.536 × 10¹⁰⁴(105-digit number)
25362898868289815846…21554859034641694719
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:57,670,508 XPM·at block #6,803,309 · updates every 60s
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