Block #330,016

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/26/2013, 9:19:06 AM · Difficulty 10.1685 · 6,475,085 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
3c250313912c593b5713a4f3f145623d966655d14e0fecbaaba0b6949df60636

Height

#330,016

Difficulty

10.168544

Transactions

16

Size

9.28 KB

Version

2

Bits

0a2b25b6

Nonce

25,177

Timestamp

12/26/2013, 9:19:06 AM

Confirmations

6,475,085

Merkle Root

ea3248fea55510455255a7a84c18dd9f19842061a4cdc499d7eb44f68aa8c668
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.

3.051 × 10⁹⁵(96-digit number)
30514239687024915540…70403820514634425759
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
3.051 × 10⁹⁵(96-digit number)
30514239687024915540…70403820514634425759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.102 × 10⁹⁵(96-digit number)
61028479374049831080…40807641029268851519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.220 × 10⁹⁶(97-digit number)
12205695874809966216…81615282058537703039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.441 × 10⁹⁶(97-digit number)
24411391749619932432…63230564117075406079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.882 × 10⁹⁶(97-digit number)
48822783499239864864…26461128234150812159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.764 × 10⁹⁶(97-digit number)
97645566998479729728…52922256468301624319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.952 × 10⁹⁷(98-digit number)
19529113399695945945…05844512936603248639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.905 × 10⁹⁷(98-digit number)
39058226799391891891…11689025873206497279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.811 × 10⁹⁷(98-digit number)
78116453598783783782…23378051746412994559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.562 × 10⁹⁸(99-digit number)
15623290719756756756…46756103492825989119
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:57,684,875 XPM·at block #6,805,100 · updates every 60s
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