Block #440,229

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/12/2014, 7:07:10 AM · Difficulty 10.3508 · 6,355,905 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
239cc56ec1d5030771a25937f9c2432349ea47344ada85533b5d6f790f35c857

Height

#440,229

Difficulty

10.350775

Transactions

8

Size

27.48 KB

Version

2

Bits

0a59cc5e

Nonce

7,421

Timestamp

3/12/2014, 7:07:10 AM

Confirmations

6,355,905

Merkle Root

f26162cdef20a39455d30d98b4f4a9af2ecc7895bdf7935fbbf36c50ce4cdb30
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.

5.171 × 10¹⁰⁰(101-digit number)
51714483850030710602…15934640337060739559
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
5.171 × 10¹⁰⁰(101-digit number)
51714483850030710602…15934640337060739559
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.171 × 10¹⁰⁰(101-digit number)
51714483850030710602…15934640337060739561
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
1.034 × 10¹⁰¹(102-digit number)
10342896770006142120…31869280674121479119
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.034 × 10¹⁰¹(102-digit number)
10342896770006142120…31869280674121479121
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
2.068 × 10¹⁰¹(102-digit number)
20685793540012284241…63738561348242958239
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.068 × 10¹⁰¹(102-digit number)
20685793540012284241…63738561348242958241
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
4.137 × 10¹⁰¹(102-digit number)
41371587080024568482…27477122696485916479
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.137 × 10¹⁰¹(102-digit number)
41371587080024568482…27477122696485916481
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
8.274 × 10¹⁰¹(102-digit number)
82743174160049136964…54954245392971832959
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.274 × 10¹⁰¹(102-digit number)
82743174160049136964…54954245392971832961
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:57,613,068 XPM·at block #6,796,133 · updates every 60s
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