Block #431,033

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/5/2014, 9:54:39 PM · Difficulty 10.3453 · 6,372,640 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
04b5432c95249a96798ca9e044f5dbae3a28c8747d57fcb8550c112597cd999e

Height

#431,033

Difficulty

10.345254

Transactions

4

Size

1.54 KB

Version

2

Bits

0a586295

Nonce

59,982

Timestamp

3/5/2014, 9:54:39 PM

Confirmations

6,372,640

Merkle Root

07df93177f6389b30f13d29b0fac15399d5ec18abbe2d53c069596647d196ba2
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.

9.938 × 10¹⁰²(103-digit number)
99387196970563891724…95721223594155586719
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
9.938 × 10¹⁰²(103-digit number)
99387196970563891724…95721223594155586719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.987 × 10¹⁰³(104-digit number)
19877439394112778344…91442447188311173439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.975 × 10¹⁰³(104-digit number)
39754878788225556689…82884894376622346879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.950 × 10¹⁰³(104-digit number)
79509757576451113379…65769788753244693759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.590 × 10¹⁰⁴(105-digit number)
15901951515290222675…31539577506489387519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.180 × 10¹⁰⁴(105-digit number)
31803903030580445351…63079155012978775039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.360 × 10¹⁰⁴(105-digit number)
63607806061160890703…26158310025957550079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.272 × 10¹⁰⁵(106-digit number)
12721561212232178140…52316620051915100159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.544 × 10¹⁰⁵(106-digit number)
25443122424464356281…04633240103830200319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.088 × 10¹⁰⁵(106-digit number)
50886244848928712562…09266480207660400639
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:57,673,421 XPM·at block #6,803,672 · updates every 60s
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