Home/Chain Registry/Block #418,681

Block #418,681

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/25/2014, 1:56:31 AM · Difficulty 10.3849 · 6,379,519 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
609389d5184bf6d1f5b21d5ab5ac95e4a9e6165dc31665296d294726bf8403f7

Height

#418,681

Difficulty

10.384937

Transactions

8

Size

2.60 KB

Version

2

Bits

0a628b38

Nonce

5,225

Timestamp

2/25/2014, 1:56:31 AM

Confirmations

6,379,519

Merkle Root

38c8b405eb2e9df912b1a1789c363f4744e6c2f2da60516302c80f0512e2e2ba
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.

1.329 × 10¹⁰⁰(101-digit number)
13297518844068945150…79969491172396619520
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
1.329 × 10¹⁰⁰(101-digit number)
13297518844068945150…79969491172396619519
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.329 × 10¹⁰⁰(101-digit number)
13297518844068945150…79969491172396619521
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
2.659 × 10¹⁰⁰(101-digit number)
26595037688137890300…59938982344793239039
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.659 × 10¹⁰⁰(101-digit number)
26595037688137890300…59938982344793239041
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
5.319 × 10¹⁰⁰(101-digit number)
53190075376275780600…19877964689586478079
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.319 × 10¹⁰⁰(101-digit number)
53190075376275780600…19877964689586478081
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
1.063 × 10¹⁰¹(102-digit number)
10638015075255156120…39755929379172956159
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.063 × 10¹⁰¹(102-digit number)
10638015075255156120…39755929379172956161
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
2.127 × 10¹⁰¹(102-digit number)
21276030150510312240…79511858758345912319
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.127 × 10¹⁰¹(102-digit number)
21276030150510312240…79511858758345912321
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 418681

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 609389d5184bf6d1f5b21d5ab5ac95e4a9e6165dc31665296d294726bf8403f7

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 #418,681 on Chainz ↗
Circulating Supply:57,629,606 XPM·at block #6,798,199 · updates every 60s
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