Block #433,973

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/7/2014, 11:01:23 PM · Difficulty 10.3459 · 6,363,905 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
67576de76e4e677445be5beff9953bc2de3164d32aa120f6f110705945ae07b6

Height

#433,973

Difficulty

10.345866

Transactions

3

Size

1.29 KB

Version

2

Bits

0a588aac

Nonce

267,358

Timestamp

3/7/2014, 11:01:23 PM

Confirmations

6,363,905

Merkle Root

82cb6353948e7917c7d7d40ceae8f609bb7a3af0d7169ba27f24d2bd7c5bf073
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.

4.098 × 10⁹⁷(98-digit number)
40986166787960238021…16960486029852125899
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
4.098 × 10⁹⁷(98-digit number)
40986166787960238021…16960486029852125899
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.197 × 10⁹⁷(98-digit number)
81972333575920476043…33920972059704251799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.639 × 10⁹⁸(99-digit number)
16394466715184095208…67841944119408503599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.278 × 10⁹⁸(99-digit number)
32788933430368190417…35683888238817007199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.557 × 10⁹⁸(99-digit number)
65577866860736380834…71367776477634014399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.311 × 10⁹⁹(100-digit number)
13115573372147276166…42735552955268028799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.623 × 10⁹⁹(100-digit number)
26231146744294552333…85471105910536057599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.246 × 10⁹⁹(100-digit number)
52462293488589104667…70942211821072115199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.049 × 10¹⁰⁰(101-digit number)
10492458697717820933…41884423642144230399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.098 × 10¹⁰⁰(101-digit number)
20984917395435641867…83768847284288460799
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:57,627,013 XPM·at block #6,797,877 · updates every 60s
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