Block #341,070

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/3/2014, 5:34:03 AM · Difficulty 10.1321 · 6,464,623 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4472c8f95fbcf5f9320e529f10a941df7459e73a5566e2ca5aa859e779eb509b

Height

#341,070

Difficulty

10.132074

Transactions

11

Size

13.35 KB

Version

2

Bits

0a21cf97

Nonce

67,119

Timestamp

1/3/2014, 5:34:03 AM

Confirmations

6,464,623

Merkle Root

e4b10464c0fe221bcff76c9ca6681ca72d08469c498d94b7c882982788ba5aa7
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.

7.541 × 10⁹⁵(96-digit number)
75415650344281625628…71592560914123690959
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
7.541 × 10⁹⁵(96-digit number)
75415650344281625628…71592560914123690959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.508 × 10⁹⁶(97-digit number)
15083130068856325125…43185121828247381919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.016 × 10⁹⁶(97-digit number)
30166260137712650251…86370243656494763839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
6.033 × 10⁹⁶(97-digit number)
60332520275425300502…72740487312989527679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.206 × 10⁹⁷(98-digit number)
12066504055085060100…45480974625979055359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.413 × 10⁹⁷(98-digit number)
24133008110170120201…90961949251958110719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.826 × 10⁹⁷(98-digit number)
48266016220340240402…81923898503916221439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.653 × 10⁹⁷(98-digit number)
96532032440680480804…63847797007832442879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.930 × 10⁹⁸(99-digit number)
19306406488136096160…27695594015664885759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.861 × 10⁹⁸(99-digit number)
38612812976272192321…55391188031329771519
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:57,689,626 XPM·at block #6,805,692 · updates every 60s
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