Block #396,932

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/9/2014, 5:41:51 PM · Difficulty 10.4167 · 6,414,076 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
753df046dde76c950ee22d404f8424e1c3d2d22adb0a3d81ae938d051860292b

Height

#396,932

Difficulty

10.416716

Transactions

1

Size

934 B

Version

2

Bits

0a6aadeb

Nonce

1,501,518

Timestamp

2/9/2014, 5:41:51 PM

Confirmations

6,414,076

Merkle Root

2a9947b9ed303f8529cd7a45366c6eb89035dce3e2e74dad4be75475d6d0a71b
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.

6.521 × 10⁹¹(92-digit number)
65217305250987185904…54659969341827452999
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
6.521 × 10⁹¹(92-digit number)
65217305250987185904…54659969341827452999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.304 × 10⁹²(93-digit number)
13043461050197437180…09319938683654905999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.608 × 10⁹²(93-digit number)
26086922100394874361…18639877367309811999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.217 × 10⁹²(93-digit number)
52173844200789748723…37279754734619623999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.043 × 10⁹³(94-digit number)
10434768840157949744…74559509469239247999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.086 × 10⁹³(94-digit number)
20869537680315899489…49119018938478495999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.173 × 10⁹³(94-digit number)
41739075360631798978…98238037876956991999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.347 × 10⁹³(94-digit number)
83478150721263597957…96476075753913983999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.669 × 10⁹⁴(95-digit number)
16695630144252719591…92952151507827967999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.339 × 10⁹⁴(95-digit number)
33391260288505439183…85904303015655935999
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:57,732,168 XPM·at block #6,811,007 · 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.

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

·Privacy Policy