Block #587,895

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 6/14/2014, 5:06:02 AM · Difficulty 10.9505 · 6,217,168 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
af39eb77e9dfa88e21258047eca9d478bf9d30302327fd90aeba466be620108d

Height

#587,895

Difficulty

10.950491

Transactions

7

Size

1.85 KB

Version

2

Bits

0af3535d

Nonce

160,022,765

Timestamp

6/14/2014, 5:06:02 AM

Confirmations

6,217,168

Merkle Root

0377d92737b5f6aa2f4b692dbc0c713826b1a2cd966ec40c4746abbc00fbae41
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.

9.525 × 10⁹⁹(100-digit number)
95250155395512166812…81944374531729510401
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
9.525 × 10⁹⁹(100-digit number)
95250155395512166812…81944374531729510401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
1.905 × 10¹⁰⁰(101-digit number)
19050031079102433362…63888749063459020801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
3.810 × 10¹⁰⁰(101-digit number)
38100062158204866724…27777498126918041601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
7.620 × 10¹⁰⁰(101-digit number)
76200124316409733449…55554996253836083201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
1.524 × 10¹⁰¹(102-digit number)
15240024863281946689…11109992507672166401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
3.048 × 10¹⁰¹(102-digit number)
30480049726563893379…22219985015344332801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
6.096 × 10¹⁰¹(102-digit number)
60960099453127786759…44439970030688665601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.219 × 10¹⁰²(103-digit number)
12192019890625557351…88879940061377331201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
2.438 × 10¹⁰²(103-digit number)
24384039781251114703…77759880122754662401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
4.876 × 10¹⁰²(103-digit number)
48768079562502229407…55519760245509324801
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 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
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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,684,570 XPM·at block #6,805,062 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.