Block #93,450

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 8/2/2013, 10:41:46 AM · Difficulty 9.1962 · 6,701,601 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
f021ad6c1b61e04d4b03ed7cde6884566a386d9d408d0962e367c6377506c8b3

Height

#93,450

Difficulty

9.196219

Transactions

2

Size

432 B

Version

2

Bits

09323b65

Nonce

43,117

Timestamp

8/2/2013, 10:41:46 AM

Confirmations

6,701,601

Merkle Root

5c8444de5acda50d7e12b75af78fcc323de722ab69d930c690949a4acbf7b5e9
Transactions (2)
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.

2.524 × 10¹¹⁰(111-digit number)
25249151317742457008…94992068465194745739
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
2.524 × 10¹¹⁰(111-digit number)
25249151317742457008…94992068465194745739
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.524 × 10¹¹⁰(111-digit number)
25249151317742457008…94992068465194745741
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
5.049 × 10¹¹⁰(111-digit number)
50498302635484914017…89984136930389491479
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.049 × 10¹¹⁰(111-digit number)
50498302635484914017…89984136930389491481
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
1.009 × 10¹¹¹(112-digit number)
10099660527096982803…79968273860778982959
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.009 × 10¹¹¹(112-digit number)
10099660527096982803…79968273860778982961
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
2.019 × 10¹¹¹(112-digit number)
20199321054193965607…59936547721557965919
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.019 × 10¹¹¹(112-digit number)
20199321054193965607…59936547721557965921
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
4.039 × 10¹¹¹(112-digit number)
40398642108387931214…19873095443115931839
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,604,448 XPM·at block #6,795,050 · updates every 60s
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