Block #477,048

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/6/2014, 5:55:31 AM · Difficulty 10.4750 · 6,328,994 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2970b8e802e6e5161dd9a0bd251f730b63de05489133674f8c53a378c7cbafc0

Height

#477,048

Difficulty

10.474954

Transactions

4

Size

2.43 KB

Version

2

Bits

0a799694

Nonce

24,053

Timestamp

4/6/2014, 5:55:31 AM

Confirmations

6,328,994

Merkle Root

95e5f70b914444f5c156120143dada9fafe6887c7a91b4834ff02e9b7b216874
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.

6.074 × 10⁹⁸(99-digit number)
60746239658234892089…72070548656496093439
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
6.074 × 10⁹⁸(99-digit number)
60746239658234892089…72070548656496093439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.214 × 10⁹⁹(100-digit number)
12149247931646978417…44141097312992186879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.429 × 10⁹⁹(100-digit number)
24298495863293956835…88282194625984373759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.859 × 10⁹⁹(100-digit number)
48596991726587913671…76564389251968747519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.719 × 10⁹⁹(100-digit number)
97193983453175827342…53128778503937495039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.943 × 10¹⁰⁰(101-digit number)
19438796690635165468…06257557007874990079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.887 × 10¹⁰⁰(101-digit number)
38877593381270330937…12515114015749980159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.775 × 10¹⁰⁰(101-digit number)
77755186762540661874…25030228031499960319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.555 × 10¹⁰¹(102-digit number)
15551037352508132374…50060456062999920639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.110 × 10¹⁰¹(102-digit number)
31102074705016264749…00120912125999841279
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:57,692,417 XPM·at block #6,806,041 · updates every 60s
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