Block #494,349

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/16/2014, 3:21:35 AM · Difficulty 10.7168 · 6,317,980 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
bdee5bc96ea050a557a8d1d2d68e37e7796a060e86fef0ea3b56324cccfa667a

Height

#494,349

Difficulty

10.716805

Transactions

1

Size

971 B

Version

2

Bits

0ab78089

Nonce

89,626

Timestamp

4/16/2014, 3:21:35 AM

Confirmations

6,317,980

Merkle Root

ece849f64231bd0e8f43af6ea20e0e2a8c9d3e3d524f44b43461753af3d09747
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.

9.169 × 10⁹⁸(99-digit number)
91698261978954404893…11618370598481735679
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
9.169 × 10⁹⁸(99-digit number)
91698261978954404893…11618370598481735679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.833 × 10⁹⁹(100-digit number)
18339652395790880978…23236741196963471359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.667 × 10⁹⁹(100-digit number)
36679304791581761957…46473482393926942719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.335 × 10⁹⁹(100-digit number)
73358609583163523914…92946964787853885439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.467 × 10¹⁰⁰(101-digit number)
14671721916632704782…85893929575707770879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.934 × 10¹⁰⁰(101-digit number)
29343443833265409565…71787859151415541759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.868 × 10¹⁰⁰(101-digit number)
58686887666530819131…43575718302831083519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.173 × 10¹⁰¹(102-digit number)
11737377533306163826…87151436605662167039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.347 × 10¹⁰¹(102-digit number)
23474755066612327652…74302873211324334079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.694 × 10¹⁰¹(102-digit number)
46949510133224655305…48605746422648668159
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:57,742,649 XPM·at block #6,812,328 · updates every 60s
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