Home/Chain Registry/Block #153,490

Block #153,490

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 9/7/2013, 12:58:01 AM · Difficulty 9.8636 · 6,643,325 confirmations

1CC
Cunningham Chain of the First Kind

A sequence where each prime is double the previous prime plus one.

Block Header
Block Hash
6c604e4c3ceb66d07957301c2e4db434aefbb42c853d57f770c756accd9fcada

Height

#153,490

Difficulty

9.863580

Transactions

5

Size

1.37 KB

Version

2

Bits

09dd139a

Nonce

263,320

Timestamp

9/7/2013, 12:58:01 AM

Confirmations

6,643,325

Merkle Root

98ac356512a144bafe8edda592b3aa310d9c712b0cbd1683723faa3cb9d9fb77
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.

2.325 × 10⁹⁵(96-digit number)
23255347965194465427…55703093559082764160
Discovered Prime Numbers
p_k = 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.

1
origin − 1
2.325 × 10⁹⁵(96-digit number)
23255347965194465427…55703093559082764159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.651 × 10⁹⁵(96-digit number)
46510695930388930855…11406187118165528319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.302 × 10⁹⁵(96-digit number)
93021391860777861711…22812374236331056639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.860 × 10⁹⁶(97-digit number)
18604278372155572342…45624748472662113279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.720 × 10⁹⁶(97-digit number)
37208556744311144684…91249496945324226559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.441 × 10⁹⁶(97-digit number)
74417113488622289369…82498993890648453119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.488 × 10⁹⁷(98-digit number)
14883422697724457873…64997987781296906239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.976 × 10⁹⁷(98-digit number)
29766845395448915747…29995975562593812479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.953 × 10⁹⁷(98-digit number)
59533690790897831495…59991951125187624959
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 Cunningham Chain of the First Kind. 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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 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 153490

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 6c604e4c3ceb66d07957301c2e4db434aefbb42c853d57f770c756accd9fcada

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 #153,490 on Chainz ↗
Circulating Supply:57,618,528 XPM·at block #6,796,814 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.