A308596 a(n) is the product of the prime(n) smallest primes other than prime(n).

15, 70, 6006, 1385670, 674612557710, 1006366256282310, 6899316550553351234310, 29365306848773629524600810, 1033423560710676120463066852232970, 1090001884152331303039489872122195258388782310

Offset: 1

Author

Francesco Vissani, Jun 09 2019

Keywords

• nonn

Examples

			  |    p =   |    a(n) = product of p smallest
n | prime(n) |            primes other than p
--+----------+--------------------------------------------
1 |     2    |      15 =     3 * 5
2 |     3    |      70 = 2     * 5 * 7
3 |     5    |    6006 = 2 * 3     * 7 * 11 * 13
4 |     7    | 1385670 = 2 * 3 * 5     * 11 * 13 * 17 * 19
		

Crossrefs

Cf. A002110, A306237.

Programs

Mathematica

Table[a[i]=Product[Prime[j],{j,1,Prime[i]+1}]/Prime[i],{i,10}]

Formula

a(n) = prime(prime(n)+1)#/prime(n).