Block #416,034

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/23/2014, 3:44:41 AM · Difficulty 10.3985 · 6,390,180 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c897688b8b0e66ec6bd1e65ec333234b4c0d4e1de6eac5085993bbd21858ff59

Height

#416,034

Difficulty

10.398507

Transactions

2

Size

825 B

Version

2

Bits

0a660489

Nonce

201,576

Timestamp

2/23/2014, 3:44:41 AM

Confirmations

6,390,180

Merkle Root

cc6e0274bbd88095b06b01d8500e8a9a2f95a1bb6a4fbe32dd84a166b5634f9f
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.

7.062 × 10⁹⁸(99-digit number)
70625470039015044386…75470908330027028479
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
7.062 × 10⁹⁸(99-digit number)
70625470039015044386…75470908330027028479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.412 × 10⁹⁹(100-digit number)
14125094007803008877…50941816660054056959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.825 × 10⁹⁹(100-digit number)
28250188015606017754…01883633320108113919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.650 × 10⁹⁹(100-digit number)
56500376031212035509…03767266640216227839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.130 × 10¹⁰⁰(101-digit number)
11300075206242407101…07534533280432455679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.260 × 10¹⁰⁰(101-digit number)
22600150412484814203…15069066560864911359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.520 × 10¹⁰⁰(101-digit number)
45200300824969628407…30138133121729822719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.040 × 10¹⁰⁰(101-digit number)
90400601649939256814…60276266243459645439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.808 × 10¹⁰¹(102-digit number)
18080120329987851362…20552532486919290879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.616 × 10¹⁰¹(102-digit number)
36160240659975702725…41105064973838581759
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:57,693,792 XPM·at block #6,806,213 · updates every 60s
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