Home/Chain Registry/Block #66,412

Block #66,412

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 7/19/2013, 5:18:37 PM · Difficulty 8.9861 · 6,723,638 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
eaa5c4fec71c17dd9f6db6cbc916be7f1300254483b814c61b63365d8ef40ed4

Height

#66,412

Difficulty

8.986135

Transactions

1

Size

200 B

Version

2

Bits

08fc7350

Nonce

800

Timestamp

7/19/2013, 5:18:37 PM

Confirmations

6,723,638

Merkle Root

292d709fbdda1e2ae856e4ec2bc15279e3a24054778fb6e130a130d1657d105e
Transactions (1)
1 in → 1 out12.3700 XPM110 B
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.

1.734 × 10⁹⁵(96-digit number)
17348291061486731075…31353096698865862320
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
1.734 × 10⁹⁵(96-digit number)
17348291061486731075…31353096698865862319
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.734 × 10⁹⁵(96-digit number)
17348291061486731075…31353096698865862321
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
3.469 × 10⁹⁵(96-digit number)
34696582122973462151…62706193397731724639
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.469 × 10⁹⁵(96-digit number)
34696582122973462151…62706193397731724641
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
6.939 × 10⁹⁵(96-digit number)
69393164245946924303…25412386795463449279
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
6.939 × 10⁹⁵(96-digit number)
69393164245946924303…25412386795463449281
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
1.387 × 10⁹⁶(97-digit number)
13878632849189384860…50824773590926898559
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.387 × 10⁹⁶(97-digit number)
13878632849189384860…50824773590926898561
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
2.775 × 10⁹⁶(97-digit number)
27757265698378769721…01649547181853797119
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.

View full Prime Chain Discovery page →
★☆☆☆☆
Rarity
CommonChain length 9
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
Verify on a Primecoin Node

Anyone running a Primecoin node can independently verify this block using the following RPC commands. Run these from the primecoin-cli command line or via the debug console in the Primecoin wallet.

1. Get block hash by height
getblockhash 66412

Returns the block hash for a given block height. Use this to confirm the hash shown above matches the chain.

2. Get full block data
getblock eaa5c4fec71c17dd9f6db6cbc916be7f1300254483b814c61b63365d8ef40ed4

Returns the full block header including difficulty, prime chain origin, prime chain type, transaction IDs, and all other fields shown on this page.

How to run these commands: To verify this data independently, open a terminal on your own Primecoin node and run primecoin-cli <command>. Alternatively, open the Primecoin-Qt wallet, go to Help → Debug Window → Console, and type the command directly. The node must be fully synced to this block height for the commands to return results.

Cross-reference on Chainz Explorer

Chainz is an independent Primecoin block explorer. Compare this block's data to verify accuracy.

View Block #66,412 on Chainz ↗
Circulating Supply:57,564,372 XPM·at block #6,790,049 · updates every 60s