Block #335,310

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/30/2013, 3:23:50 AM · Difficulty 10.1524 · 6,461,208 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
83679f61b4d302eb0d3c9b304f5f80f2af0c424fdabe0d9ac1d34920e6dff036

Height

#335,310

Difficulty

10.152438

Transactions

14

Size

5.38 KB

Version

2

Bits

0a27062f

Nonce

66,621

Timestamp

12/30/2013, 3:23:50 AM

Confirmations

6,461,208

Merkle Root

bae5d6db8537a8f7a1d37be7b524e6ef52b2ed4bbd163181c1712f3ab027666c
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.

3.415 × 10¹⁰²(103-digit number)
34154241749710297540…83973186619708743679
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
3.415 × 10¹⁰²(103-digit number)
34154241749710297540…83973186619708743679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.830 × 10¹⁰²(103-digit number)
68308483499420595081…67946373239417487359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.366 × 10¹⁰³(104-digit number)
13661696699884119016…35892746478834974719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.732 × 10¹⁰³(104-digit number)
27323393399768238032…71785492957669949439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.464 × 10¹⁰³(104-digit number)
54646786799536476065…43570985915339898879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.092 × 10¹⁰⁴(105-digit number)
10929357359907295213…87141971830679797759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.185 × 10¹⁰⁴(105-digit number)
21858714719814590426…74283943661359595519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.371 × 10¹⁰⁴(105-digit number)
43717429439629180852…48567887322719191039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.743 × 10¹⁰⁴(105-digit number)
87434858879258361704…97135774645438382079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.748 × 10¹⁰⁵(106-digit number)
17486971775851672340…94271549290876764159
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:57,616,141 XPM·at block #6,796,517 · updates every 60s
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