Home/Chain Registry/Block #286,913

Block #286,913

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 12/1/2013, 2:29:15 AM · Difficulty 9.9861 · 6,512,364 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
4cc47d2373b2770312a0093e99c5de8ad26a9ab81940072bdbd4ce979c762fd2

Height

#286,913

Difficulty

9.986122

Transactions

16

Size

7.81 KB

Version

2

Bits

09fc7280

Nonce

20,939

Timestamp

12/1/2013, 2:29:15 AM

Confirmations

6,512,364

Merkle Root

f68b1f78392f3b2ab495e6a8e34950901f7564a5af06dfedfca37148b6d488c4
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.

3.468 × 10⁹⁷(98-digit number)
34683599734375450487…97510811888637485600
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
3.468 × 10⁹⁷(98-digit number)
34683599734375450487…97510811888637485599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.468 × 10⁹⁷(98-digit number)
34683599734375450487…97510811888637485601
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
6.936 × 10⁹⁷(98-digit number)
69367199468750900975…95021623777274971199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.936 × 10⁹⁷(98-digit number)
69367199468750900975…95021623777274971201
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
1.387 × 10⁹⁸(99-digit number)
13873439893750180195…90043247554549942399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.387 × 10⁹⁸(99-digit number)
13873439893750180195…90043247554549942401
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
2.774 × 10⁹⁸(99-digit number)
27746879787500360390…80086495109099884799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.774 × 10⁹⁸(99-digit number)
27746879787500360390…80086495109099884801
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
5.549 × 10⁹⁸(99-digit number)
55493759575000720780…60172990218199769599
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 286913

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 4cc47d2373b2770312a0093e99c5de8ad26a9ab81940072bdbd4ce979c762fd2

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 #286,913 on Chainz ↗
Circulating Supply:57,638,257 XPM·at block #6,799,276 · updates every 60s
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