Home/Chain Registry/Block #475,320

Block #475,320

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/5/2014, 4:06:54 AM · Difficulty 10.4556 · 6,320,857 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
f044bca680ef6bb2b102f6635098abbd0bae5e010fcf802857ceefc17b00bd9a

Height

#475,320

Difficulty

10.455575

Transactions

1

Size

1004 B

Version

2

Bits

0a74a08e

Nonce

44,368

Timestamp

4/5/2014, 4:06:54 AM

Confirmations

6,320,857

Merkle Root

07ab58e585ba324adc5e22b8b4bf768ea5401568efb6837e27d9f82ec8c013d3
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.

8.759 × 10⁹⁷(98-digit number)
87590066226141685895…07513010433755469440
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
8.759 × 10⁹⁷(98-digit number)
87590066226141685895…07513010433755469439
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
8.759 × 10⁹⁷(98-digit number)
87590066226141685895…07513010433755469441
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
1.751 × 10⁹⁸(99-digit number)
17518013245228337179…15026020867510938879
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.751 × 10⁹⁸(99-digit number)
17518013245228337179…15026020867510938881
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
3.503 × 10⁹⁸(99-digit number)
35036026490456674358…30052041735021877759
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.503 × 10⁹⁸(99-digit number)
35036026490456674358…30052041735021877761
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
7.007 × 10⁹⁸(99-digit number)
70072052980913348716…60104083470043755519
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.007 × 10⁹⁸(99-digit number)
70072052980913348716…60104083470043755521
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
1.401 × 10⁹⁹(100-digit number)
14014410596182669743…20208166940087511039
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.401 × 10⁹⁹(100-digit number)
14014410596182669743…20208166940087511041
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.

View full Prime Chain Discovery page →
★★☆☆☆
Rarity
UncommonChain length 10
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 475320

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 f044bca680ef6bb2b102f6635098abbd0bae5e010fcf802857ceefc17b00bd9a

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 #475,320 on Chainz ↗
Circulating Supply:57,613,415 XPM·at block #6,796,176 · updates every 60s
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