Block #270,042

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/23/2013, 4:06:25 PM · Difficulty 9.9512 · 6,533,342 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
2bb5e7f47a54675fc9a0664239db5d5fe2ac8116619212eb35fb80db610bba93

Height

#270,042

Difficulty

9.951175

Transactions

10

Size

6.69 KB

Version

2

Bits

09f38030

Nonce

35,520

Timestamp

11/23/2013, 4:06:25 PM

Confirmations

6,533,342

Merkle Root

cc973828d3144cf077feb7577654560e6ac8454268abd158dfec32a7eca52ba5
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.

6.992 × 10⁹⁶(97-digit number)
69922121531833658103…68159620244668630839
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
6.992 × 10⁹⁶(97-digit number)
69922121531833658103…68159620244668630839
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
6.992 × 10⁹⁶(97-digit number)
69922121531833658103…68159620244668630841
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
1.398 × 10⁹⁷(98-digit number)
13984424306366731620…36319240489337261679
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.398 × 10⁹⁷(98-digit number)
13984424306366731620…36319240489337261681
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
2.796 × 10⁹⁷(98-digit number)
27968848612733463241…72638480978674523359
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.796 × 10⁹⁷(98-digit number)
27968848612733463241…72638480978674523361
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
5.593 × 10⁹⁷(98-digit number)
55937697225466926482…45276961957349046719
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
5.593 × 10⁹⁷(98-digit number)
55937697225466926482…45276961957349046721
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
1.118 × 10⁹⁸(99-digit number)
11187539445093385296…90553923914698093439
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.118 × 10⁹⁸(99-digit number)
11187539445093385296…90553923914698093441
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:57,671,109 XPM·at block #6,803,383 · updates every 60s
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