Block #360,854

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/15/2014, 5:06:06 PM · Difficulty 10.3991 · 6,444,323 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
942204f9605ce0d3db75d95c8d05afa1532b9665b07dcd34c0ebfa948adbb533

Height

#360,854

Difficulty

10.399138

Transactions

6

Size

1.70 KB

Version

2

Bits

0a662dec

Nonce

74,375

Timestamp

1/15/2014, 5:06:06 PM

Confirmations

6,444,323

Merkle Root

49768efdaa6dc9b1429f431fed55cd99bab8998cf9509274dc8257f9ca2fd2a0
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.

2.814 × 10⁹⁰(91-digit number)
28148555106253054918…17882363085975794649
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
2.814 × 10⁹⁰(91-digit number)
28148555106253054918…17882363085975794649
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.629 × 10⁹⁰(91-digit number)
56297110212506109836…35764726171951589299
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.125 × 10⁹¹(92-digit number)
11259422042501221967…71529452343903178599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.251 × 10⁹¹(92-digit number)
22518844085002443934…43058904687806357199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.503 × 10⁹¹(92-digit number)
45037688170004887869…86117809375612714399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.007 × 10⁹¹(92-digit number)
90075376340009775738…72235618751225428799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.801 × 10⁹²(93-digit number)
18015075268001955147…44471237502450857599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.603 × 10⁹²(93-digit number)
36030150536003910295…88942475004901715199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.206 × 10⁹²(93-digit number)
72060301072007820590…77884950009803430399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.441 × 10⁹³(94-digit number)
14412060214401564118…55769900019606860799
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:57,685,485 XPM·at block #6,805,176 · updates every 60s
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