Block #341,708

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/3/2014, 3:15:56 PM · Difficulty 10.1429 · 6,461,678 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a4480e0f95ddb588ee874a3487cceabb2d69c4e2564b077d37fde56469343d53

Height

#341,708

Difficulty

10.142869

Transactions

15

Size

183.02 KB

Version

2

Bits

0a249313

Nonce

736,831

Timestamp

1/3/2014, 3:15:56 PM

Confirmations

6,461,678

Merkle Root

3fff43febcb2aff1be72cd3c11d9c979bd107e9fe5db365e03b50bcb8a15b87a
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.

1.198 × 10¹⁰²(103-digit number)
11984977433089449785…97853416444862330879
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
1.198 × 10¹⁰²(103-digit number)
11984977433089449785…97853416444862330879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.396 × 10¹⁰²(103-digit number)
23969954866178899570…95706832889724661759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.793 × 10¹⁰²(103-digit number)
47939909732357799141…91413665779449323519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.587 × 10¹⁰²(103-digit number)
95879819464715598282…82827331558898647039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.917 × 10¹⁰³(104-digit number)
19175963892943119656…65654663117797294079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.835 × 10¹⁰³(104-digit number)
38351927785886239313…31309326235594588159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.670 × 10¹⁰³(104-digit number)
76703855571772478626…62618652471189176319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.534 × 10¹⁰⁴(105-digit number)
15340771114354495725…25237304942378352639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.068 × 10¹⁰⁴(105-digit number)
30681542228708991450…50474609884756705279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.136 × 10¹⁰⁴(105-digit number)
61363084457417982900…00949219769513410559
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:57,671,116 XPM·at block #6,803,385 · updates every 60s
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