Block #461,604

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/26/2014, 8:32:18 PM · Difficulty 10.4143 · 6,340,947 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e6bbcae3c74acf2865858d1ed5986f8b7abf6bc4caf7b559374b681661cbb25e

Height

#461,604

Difficulty

10.414306

Transactions

9

Size

4.86 KB

Version

2

Bits

0a6a0ff6

Nonce

370,183

Timestamp

3/26/2014, 8:32:18 PM

Confirmations

6,340,947

Merkle Root

b922dbf68f797d04c48956630642d6c4099880acc7de77e0264fa8b7a773aaa0
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.

6.660 × 10⁹⁸(99-digit number)
66606266219713050872…55775998085890747859
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
6.660 × 10⁹⁸(99-digit number)
66606266219713050872…55775998085890747859
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.332 × 10⁹⁹(100-digit number)
13321253243942610174…11551996171781495719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.664 × 10⁹⁹(100-digit number)
26642506487885220349…23103992343562991439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.328 × 10⁹⁹(100-digit number)
53285012975770440698…46207984687125982879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.065 × 10¹⁰⁰(101-digit number)
10657002595154088139…92415969374251965759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.131 × 10¹⁰⁰(101-digit number)
21314005190308176279…84831938748503931519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.262 × 10¹⁰⁰(101-digit number)
42628010380616352558…69663877497007863039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.525 × 10¹⁰⁰(101-digit number)
85256020761232705116…39327754994015726079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.705 × 10¹⁰¹(102-digit number)
17051204152246541023…78655509988031452159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.410 × 10¹⁰¹(102-digit number)
34102408304493082046…57311019976062904319
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:57,664,420 XPM·at block #6,802,550 · updates every 60s
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