Block #417,849

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/24/2014, 11:05:22 AM · Difficulty 10.3904 · 6,388,067 confirmations

TWN
Bi-Twin Chain

Interleaved pairs of primes that differ by 2, forming twin prime pairs at each level.

Block Header
Block Hash
bf6c1fe83ec2189493dd675c6d72bdfcf42d21424a5b162359e4a3e6eb43d25c

Height

#417,849

Difficulty

10.390394

Transactions

1

Size

903 B

Version

2

Bits

0a63f0d8

Nonce

216,622

Timestamp

2/24/2014, 11:05:22 AM

Confirmations

6,388,067

Merkle Root

3e18a1c600396d88da66a214ea4e33220e1260cc28e881e530aaa0aa3d2d026c
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.

1.591 × 10¹⁰⁰(101-digit number)
15916797664759320830…40028640156282921339
Discovered Prime Numbers
Lower: 2^k × origin − 1 | Upper: 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.

Level 0 — Twin Prime Pair (origin ± 1)
origin − 1
1.591 × 10¹⁰⁰(101-digit number)
15916797664759320830…40028640156282921339
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.591 × 10¹⁰⁰(101-digit number)
15916797664759320830…40028640156282921341
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: origin + 1 − origin − 1 = 2 (twin primes ✓)
Level 1 — Twin Prime Pair (2^1 × origin ± 1)
2^1 × origin − 1
3.183 × 10¹⁰⁰(101-digit number)
31833595329518641661…80057280312565842679
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.183 × 10¹⁰⁰(101-digit number)
31833595329518641661…80057280312565842681
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^1 × origin + 1 − 2^1 × origin − 1 = 2 (twin primes ✓)
Level 2 — Twin Prime Pair (2^2 × origin ± 1)
2^2 × origin − 1
6.366 × 10¹⁰⁰(101-digit number)
63667190659037283322…60114560625131685359
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
6.366 × 10¹⁰⁰(101-digit number)
63667190659037283322…60114560625131685361
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^2 × origin + 1 − 2^2 × origin − 1 = 2 (twin primes ✓)
Level 3 — Twin Prime Pair (2^3 × origin ± 1)
2^3 × origin − 1
1.273 × 10¹⁰¹(102-digit number)
12733438131807456664…20229121250263370719
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.273 × 10¹⁰¹(102-digit number)
12733438131807456664…20229121250263370721
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^3 × origin + 1 − 2^3 × origin − 1 = 2 (twin primes ✓)
Level 4 — Twin Prime Pair (2^4 × origin ± 1)
2^4 × origin − 1
2.546 × 10¹⁰¹(102-digit number)
25466876263614913328…40458242500526741439
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.546 × 10¹⁰¹(102-digit number)
25466876263614913328…40458242500526741441
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)

What this block proved

The miner who found this block proved the existence of 10 consecutive prime numbers forming a Bi-Twin Chain. 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 TWN formula:

TWN: twin pairs (p, p+2) where p = origin/primorial − 1 and p+2 = origin/primorial + 1
Circulating Supply:57,691,418 XPM·at block #6,805,915 · updates every 60s
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