Block #379,507

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/28/2014, 2:06:00 PM · Difficulty 10.4184 · 6,414,075 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
34cf1618c5b2ebbbd969b5b3a3b61d4f0b8234ee5f7e0fbe4cce895990b86e94

Height

#379,507

Difficulty

10.418353

Transactions

7

Size

2.89 KB

Version

2

Bits

0a6b1934

Nonce

30,511

Timestamp

1/28/2014, 2:06:00 PM

Confirmations

6,414,075

Merkle Root

eab24f661115ad1755c238eb0b952547090674f48d73620f150a1bf4b727e458
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.

4.926 × 10⁹⁸(99-digit number)
49266837291104063992…50737907779756984319
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
4.926 × 10⁹⁸(99-digit number)
49266837291104063992…50737907779756984319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.853 × 10⁹⁸(99-digit number)
98533674582208127984…01475815559513968639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.970 × 10⁹⁹(100-digit number)
19706734916441625596…02951631119027937279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.941 × 10⁹⁹(100-digit number)
39413469832883251193…05903262238055874559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.882 × 10⁹⁹(100-digit number)
78826939665766502387…11806524476111749119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.576 × 10¹⁰⁰(101-digit number)
15765387933153300477…23613048952223498239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.153 × 10¹⁰⁰(101-digit number)
31530775866306600954…47226097904446996479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.306 × 10¹⁰⁰(101-digit number)
63061551732613201909…94452195808893992959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.261 × 10¹⁰¹(102-digit number)
12612310346522640381…88904391617787985919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.522 × 10¹⁰¹(102-digit number)
25224620693045280763…77808783235575971839
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:57,592,651 XPM·at block #6,793,581 · updates every 60s
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