Block #486,690

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/11/2014, 5:45:48 PM · Difficulty 10.6299 · 6,304,465 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c37b9672bde342d5d36d5c8e4720a3b0f2f7897362e3bb21086d5d3cf5baa51d

Height

#486,690

Difficulty

10.629868

Transactions

8

Size

2.72 KB

Version

2

Bits

0aa13f00

Nonce

442,586,306

Timestamp

4/11/2014, 5:45:48 PM

Confirmations

6,304,465

Merkle Root

f1d42f8ae4c8e54a03492a9ca8088f947db1a0e242d7e8530a4d835080b34ca7
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.

1.147 × 10⁹⁹(100-digit number)
11479492472426764885…01612358932845392639
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
1.147 × 10⁹⁹(100-digit number)
11479492472426764885…01612358932845392639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.295 × 10⁹⁹(100-digit number)
22958984944853529770…03224717865690785279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.591 × 10⁹⁹(100-digit number)
45917969889707059541…06449435731381570559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.183 × 10⁹⁹(100-digit number)
91835939779414119083…12898871462763141119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.836 × 10¹⁰⁰(101-digit number)
18367187955882823816…25797742925526282239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.673 × 10¹⁰⁰(101-digit number)
36734375911765647633…51595485851052564479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.346 × 10¹⁰⁰(101-digit number)
73468751823531295266…03190971702105128959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.469 × 10¹⁰¹(102-digit number)
14693750364706259053…06381943404210257919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.938 × 10¹⁰¹(102-digit number)
29387500729412518106…12763886808420515839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.877 × 10¹⁰¹(102-digit number)
58775001458825036213…25527773616841031679
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:57,573,179 XPM·at block #6,791,154 · updates every 60s
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