Block #495,982

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/16/2014, 9:05:12 PM · Difficulty 10.7475 · 6,307,716 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
7356a6d00243dbd41ff3daa02e58f23433c12db50e2c66ac4a50ec4f8ec79452

Height

#495,982

Difficulty

10.747471

Transactions

9

Size

2.89 KB

Version

2

Bits

0abf5a3c

Nonce

41,526,572

Timestamp

4/16/2014, 9:05:12 PM

Confirmations

6,307,716

Merkle Root

be2ecc003a2c5c53808fbeb6caf38f7e807aadf0f6a5b0b31823653dfe88dfa9
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.

1.155 × 10¹⁰⁰(101-digit number)
11557831001836892553…71769077537703987199
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
1.155 × 10¹⁰⁰(101-digit number)
11557831001836892553…71769077537703987199
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.155 × 10¹⁰⁰(101-digit number)
11557831001836892553…71769077537703987201
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
2.311 × 10¹⁰⁰(101-digit number)
23115662003673785107…43538155075407974399
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.311 × 10¹⁰⁰(101-digit number)
23115662003673785107…43538155075407974401
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
4.623 × 10¹⁰⁰(101-digit number)
46231324007347570214…87076310150815948799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.623 × 10¹⁰⁰(101-digit number)
46231324007347570214…87076310150815948801
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
9.246 × 10¹⁰⁰(101-digit number)
92462648014695140428…74152620301631897599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
9.246 × 10¹⁰⁰(101-digit number)
92462648014695140428…74152620301631897601
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
1.849 × 10¹⁰¹(102-digit number)
18492529602939028085…48305240603263795199
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.849 × 10¹⁰¹(102-digit number)
18492529602939028085…48305240603263795201
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:57,673,622 XPM·at block #6,803,697 · updates every 60s
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