Block #559,619

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 5/24/2014, 7:40:10 AM · Difficulty 10.9645 · 6,246,467 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
d6939e3a8a42c41a4ebe508553ff12625a180414eb6272df00e7a9147e7e39b0

Height

#559,619

Difficulty

10.964542

Transactions

5

Size

1.34 KB

Version

2

Bits

0af6ec33

Nonce

1,039,799,195

Timestamp

5/24/2014, 7:40:10 AM

Confirmations

6,246,467

Merkle Root

3bc1bc9f77ab55ed373a3dbd274231bc568038fdb8b3d70dd6e81b3bb9e8904b
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.

7.208 × 10¹⁰⁰(101-digit number)
72085138323294052252…48630698316093757441
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
7.208 × 10¹⁰⁰(101-digit number)
72085138323294052252…48630698316093757441
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.441 × 10¹⁰¹(102-digit number)
14417027664658810450…97261396632187514881
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
2.883 × 10¹⁰¹(102-digit number)
28834055329317620901…94522793264375029761
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
5.766 × 10¹⁰¹(102-digit number)
57668110658635241802…89045586528750059521
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.153 × 10¹⁰²(103-digit number)
11533622131727048360…78091173057500119041
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
2.306 × 10¹⁰²(103-digit number)
23067244263454096720…56182346115000238081
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
4.613 × 10¹⁰²(103-digit number)
46134488526908193441…12364692230000476161
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
9.226 × 10¹⁰²(103-digit number)
92268977053816386883…24729384460000952321
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.845 × 10¹⁰³(104-digit number)
18453795410763277376…49458768920001904641
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
3.690 × 10¹⁰³(104-digit number)
36907590821526554753…98917537840003809281
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
7.381 × 10¹⁰³(104-digit number)
73815181643053109506…97835075680007618561
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:57,692,760 XPM·at block #6,806,085 · updates every 60s
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