Home/Chain Registry/Block #157,444

Block #157,444

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 9/9/2013, 3:26:37 PM · Difficulty 9.8691 · 6,638,079 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
d605c4a1925886ce1cf4bbdfdb38785fa666428126a8ee4570c386826a14c18e

Height

#157,444

Difficulty

9.869125

Transactions

9

Size

2.68 KB

Version

2

Bits

09de7f02

Nonce

89,498

Timestamp

9/9/2013, 3:26:37 PM

Confirmations

6,638,079

Merkle Root

373a07b2f90d275eed2f0cc16deda6924c208c2dfb27714546508188c0be3a19
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.

1.461 × 10⁹³(94-digit number)
14612265483656963328…50789651667320648320
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
1.461 × 10⁹³(94-digit number)
14612265483656963328…50789651667320648319
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.461 × 10⁹³(94-digit number)
14612265483656963328…50789651667320648321
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
2.922 × 10⁹³(94-digit number)
29224530967313926656…01579303334641296639
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.922 × 10⁹³(94-digit number)
29224530967313926656…01579303334641296641
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
5.844 × 10⁹³(94-digit number)
58449061934627853313…03158606669282593279
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.844 × 10⁹³(94-digit number)
58449061934627853313…03158606669282593281
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
1.168 × 10⁹⁴(95-digit number)
11689812386925570662…06317213338565186559
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.168 × 10⁹⁴(95-digit number)
11689812386925570662…06317213338565186561
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
2.337 × 10⁹⁴(95-digit number)
23379624773851141325…12634426677130373119
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 157444

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 d605c4a1925886ce1cf4bbdfdb38785fa666428126a8ee4570c386826a14c18e

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 #157,444 on Chainz ↗
Circulating Supply:57,608,246 XPM·at block #6,795,522 · updates every 60s
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