Block #412,610

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/20/2014, 3:05:42 PM · Difficulty 10.4223 · 6,382,896 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
d421ff6915f1b1aaadef106eef153d7bdeafe070e7421a3d2a893c914d907e8a

Height

#412,610

Difficulty

10.422335

Transactions

13

Size

6.16 KB

Version

2

Bits

0a6c1e24

Nonce

8,076

Timestamp

2/20/2014, 3:05:42 PM

Confirmations

6,382,896

Merkle Root

5d0254df41faacce7dcbd74db9b49f60df4dfed06a047c425f117f755721c14b
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.

5.120 × 10¹⁰¹(102-digit number)
51208894795476291757…87145361686190714949
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
5.120 × 10¹⁰¹(102-digit number)
51208894795476291757…87145361686190714949
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.024 × 10¹⁰²(103-digit number)
10241778959095258351…74290723372381429899
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.048 × 10¹⁰²(103-digit number)
20483557918190516702…48581446744762859799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.096 × 10¹⁰²(103-digit number)
40967115836381033405…97162893489525719599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.193 × 10¹⁰²(103-digit number)
81934231672762066811…94325786979051439199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.638 × 10¹⁰³(104-digit number)
16386846334552413362…88651573958102878399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.277 × 10¹⁰³(104-digit number)
32773692669104826724…77303147916205756799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.554 × 10¹⁰³(104-digit number)
65547385338209653449…54606295832411513599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.310 × 10¹⁰⁴(105-digit number)
13109477067641930689…09212591664823027199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.621 × 10¹⁰⁴(105-digit number)
26218954135283861379…18425183329646054399
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:57,608,112 XPM·at block #6,795,505 · updates every 60s
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