Home/Chain Registry/Block #160,869

Block #160,869

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 9/12/2013, 6:23:11 AM · Difficulty 9.8598 · 6,630,855 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
6f8720d1084c93c41f40a38be5ea1f4a2c1b4ba4a041a7a260b05ee6dc0be5b5

Height

#160,869

Difficulty

9.859822

Transactions

1

Size

198 B

Version

2

Bits

09dc1d4e

Nonce

19,987

Timestamp

9/12/2013, 6:23:11 AM

Confirmations

6,630,855

Merkle Root

3507a0ab66e03960bf65c53635c58a2e9e28b3cda07a3893a2e4635052b4ed6c
Transactions (1)
1 in → 1 out10.2700 XPM109 B
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.

3.631 × 10⁹¹(92-digit number)
36319493076038148583…75756046216375133750
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
3.631 × 10⁹¹(92-digit number)
36319493076038148583…75756046216375133749
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.631 × 10⁹¹(92-digit number)
36319493076038148583…75756046216375133751
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
7.263 × 10⁹¹(92-digit number)
72638986152076297167…51512092432750267499
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.263 × 10⁹¹(92-digit number)
72638986152076297167…51512092432750267501
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
1.452 × 10⁹²(93-digit number)
14527797230415259433…03024184865500534999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.452 × 10⁹²(93-digit number)
14527797230415259433…03024184865500535001
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
2.905 × 10⁹²(93-digit number)
29055594460830518867…06048369731001069999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.905 × 10⁹²(93-digit number)
29055594460830518867…06048369731001070001
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
5.811 × 10⁹²(93-digit number)
58111188921661037734…12096739462002139999
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 160869

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 6f8720d1084c93c41f40a38be5ea1f4a2c1b4ba4a041a7a260b05ee6dc0be5b5

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 #160,869 on Chainz ↗
Circulating Supply:57,577,740 XPM·at block #6,791,723 · updates every 60s
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