Block #510,487

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 4/25/2014, 4:37:32 PM · Difficulty 10.8252 · 6,282,160 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
1a8c74ca20bb0066cec3138382cfd3eef96f54bcae5e24793bb60db815c8f1e2

Height

#510,487

Difficulty

10.825204

Transactions

8

Size

3.03 KB

Version

2

Bits

0ad34091

Nonce

29,892,839

Timestamp

4/25/2014, 4:37:32 PM

Confirmations

6,282,160

Merkle Root

6fb485be71f543f1b7d021c6e0d362bf7378ffdd3bec4a84684b78996f116713
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.

3.662 × 10⁹³(94-digit number)
36622114810174129254…19592438154966197431
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
3.662 × 10⁹³(94-digit number)
36622114810174129254…19592438154966197431
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
7.324 × 10⁹³(94-digit number)
73244229620348258508…39184876309932394861
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.464 × 10⁹⁴(95-digit number)
14648845924069651701…78369752619864789721
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
2.929 × 10⁹⁴(95-digit number)
29297691848139303403…56739505239729579441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
5.859 × 10⁹⁴(95-digit number)
58595383696278606806…13479010479459158881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.171 × 10⁹⁵(96-digit number)
11719076739255721361…26958020958918317761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.343 × 10⁹⁵(96-digit number)
23438153478511442722…53916041917836635521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
4.687 × 10⁹⁵(96-digit number)
46876306957022885445…07832083835673271041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
9.375 × 10⁹⁵(96-digit number)
93752613914045770890…15664167671346542081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
1.875 × 10⁹⁶(97-digit number)
18750522782809154178…31328335342693084161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
3.750 × 10⁹⁶(97-digit number)
37501045565618308356…62656670685386168321
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 consecutive prime numbers forming a Cunningham Chain of the Second 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,585,144 XPM·at block #6,792,646 · updates every 60s
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