Block #340,039

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/2/2014, 12:47:20 PM · Difficulty 10.1276 · 6,465,820 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
88ed6ffc9b71fa31184847a003ba5bfd4211c93cd300b220fb61bdec445336de

Height

#340,039

Difficulty

10.127579

Transactions

11

Size

2.92 KB

Version

2

Bits

0a20a907

Nonce

102,426

Timestamp

1/2/2014, 12:47:20 PM

Confirmations

6,465,820

Merkle Root

94a1b83ee58f1f6b934c63994c09e03ba2fb06b3e01ae79d591f12603da4b0d8
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.

1.199 × 10¹⁰⁰(101-digit number)
11990723061044763738…97414405699907690239
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
1.199 × 10¹⁰⁰(101-digit number)
11990723061044763738…97414405699907690239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.398 × 10¹⁰⁰(101-digit number)
23981446122089527477…94828811399815380479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.796 × 10¹⁰⁰(101-digit number)
47962892244179054954…89657622799630760959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.592 × 10¹⁰⁰(101-digit number)
95925784488358109908…79315245599261521919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.918 × 10¹⁰¹(102-digit number)
19185156897671621981…58630491198523043839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.837 × 10¹⁰¹(102-digit number)
38370313795343243963…17260982397046087679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.674 × 10¹⁰¹(102-digit number)
76740627590686487926…34521964794092175359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.534 × 10¹⁰²(103-digit number)
15348125518137297585…69043929588184350719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.069 × 10¹⁰²(103-digit number)
30696251036274595170…38087859176368701439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.139 × 10¹⁰²(103-digit number)
61392502072549190341…76175718352737402879
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:57,690,954 XPM·at block #6,805,858 · updates every 60s
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