Home/Chain Registry/Block #169,336

Block #169,336

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 9/17/2013, 10:32:34 PM · Difficulty 9.8683 · 6,620,766 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
7669a807c8957ea8986c72fb4a7d8ef16757e31ed504c54a5d76ca269690c01c

Height

#169,336

Difficulty

9.868300

Transactions

2

Size

571 B

Version

2

Bits

09de48e4

Nonce

166,867

Timestamp

9/17/2013, 10:32:34 PM

Confirmations

6,620,766

Merkle Root

502e7496e86a1db695c4922b617b8447bae2687ae9d35f50cb9a5244cf4ba1b2
Transactions (2)
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.

2.043 × 10⁹⁴(95-digit number)
20435611490606917460…17655729049269570720
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
2.043 × 10⁹⁴(95-digit number)
20435611490606917460…17655729049269570719
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.043 × 10⁹⁴(95-digit number)
20435611490606917460…17655729049269570721
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
4.087 × 10⁹⁴(95-digit number)
40871222981213834921…35311458098539141439
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.087 × 10⁹⁴(95-digit number)
40871222981213834921…35311458098539141441
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
8.174 × 10⁹⁴(95-digit number)
81742445962427669843…70622916197078282879
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
8.174 × 10⁹⁴(95-digit number)
81742445962427669843…70622916197078282881
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
1.634 × 10⁹⁵(96-digit number)
16348489192485533968…41245832394156565759
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.634 × 10⁹⁵(96-digit number)
16348489192485533968…41245832394156565761
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
3.269 × 10⁹⁵(96-digit number)
32696978384971067937…82491664788313131519
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.269 × 10⁹⁵(96-digit number)
32696978384971067937…82491664788313131521
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 169336

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 7669a807c8957ea8986c72fb4a7d8ef16757e31ed504c54a5d76ca269690c01c

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 #169,336 on Chainz ↗
Circulating Supply:57,564,791 XPM·at block #6,790,101 · updates every 60s