Block #498,430

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/18/2014, 2:35:32 AM · Difficulty 10.7795 · 6,294,267 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c57ab7d38b8ecfeebedbef1d08b2cdabf51071109bd74409efa890142b666172

Height

#498,430

Difficulty

10.779481

Transactions

9

Size

1.96 KB

Version

2

Bits

0ac78c13

Nonce

430,457,071

Timestamp

4/18/2014, 2:35:32 AM

Confirmations

6,294,267

Merkle Root

648f4fb7189b9407d046e4ae056844cdf9f8ef9edf0a4abd28d65caed5a1f9ae
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.

8.483 × 10⁹³(94-digit number)
84831573683832517858…16029794254935552049
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
8.483 × 10⁹³(94-digit number)
84831573683832517858…16029794254935552049
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.696 × 10⁹⁴(95-digit number)
16966314736766503571…32059588509871104099
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.393 × 10⁹⁴(95-digit number)
33932629473533007143…64119177019742208199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.786 × 10⁹⁴(95-digit number)
67865258947066014286…28238354039484416399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.357 × 10⁹⁵(96-digit number)
13573051789413202857…56476708078968832799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.714 × 10⁹⁵(96-digit number)
27146103578826405714…12953416157937665599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
5.429 × 10⁹⁵(96-digit number)
54292207157652811429…25906832315875331199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.085 × 10⁹⁶(97-digit number)
10858441431530562285…51813664631750662399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.171 × 10⁹⁶(97-digit number)
21716882863061124571…03627329263501324799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.343 × 10⁹⁶(97-digit number)
43433765726122249143…07254658527002649599
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:57,585,551 XPM·at block #6,792,696 · updates every 60s
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