Block #429,660

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/4/2014, 10:53:14 PM · Difficulty 10.3458 · 6,369,272 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
8959d6c2db3083ad4ade873505bdda8834a09c8fb911f3d83767400b0c40f22e

Height

#429,660

Difficulty

10.345786

Transactions

1

Size

1.05 KB

Version

2

Bits

0a58856b

Nonce

15,840

Timestamp

3/4/2014, 10:53:14 PM

Confirmations

6,369,272

Merkle Root

6eea0e0caf850386be5c3df5741af1d9e01605c1b19a6ca9804bb6d2d956358d
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.

3.634 × 10⁹⁹(100-digit number)
36343095787617413549…78223591536193727679
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
3.634 × 10⁹⁹(100-digit number)
36343095787617413549…78223591536193727679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.268 × 10⁹⁹(100-digit number)
72686191575234827099…56447183072387455359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.453 × 10¹⁰⁰(101-digit number)
14537238315046965419…12894366144774910719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.907 × 10¹⁰⁰(101-digit number)
29074476630093930839…25788732289549821439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.814 × 10¹⁰⁰(101-digit number)
58148953260187861679…51577464579099642879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.162 × 10¹⁰¹(102-digit number)
11629790652037572335…03154929158199285759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.325 × 10¹⁰¹(102-digit number)
23259581304075144671…06309858316398571519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.651 × 10¹⁰¹(102-digit number)
46519162608150289343…12619716632797143039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.303 × 10¹⁰¹(102-digit number)
93038325216300578687…25239433265594286079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.860 × 10¹⁰²(103-digit number)
18607665043260115737…50478866531188572159
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:57,635,491 XPM·at block #6,798,931 · updates every 60s
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