A048148 Distinct elements of A045948.

1, 2, 4, 12, 24, 120, 360, 720, 5040, 10080, 30240, 332640, 1663200, 3326400, 43243200, 129729600, 259459200, 4410806400, 30875644800, 586637251200, 1173274502400, 26985313555200, 134926567776000, 404779703328000, 11738611396512000, 363896953291872000

Offset: 1

Author

Labos Elemer

Keywords

• nonn

Comments

A001222(a(n)) = n - 1. - Eric Desbiaux, Apr 05 2018

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..412 (terms 1..237 from Michael De Vlieger)

Crossrefs

Cf. A003418, A034386, A002110, A000142, A049536.

Programs

Mathematica

Map[Function[m, Exp[Sum[MangoldtLambda@ n, {n, m}]]/Product[x, {x, Prime@ Range@ PrimePi@ m}]], Select[Range[10^3], Or[# == 1, And[PrimePowerQ@ #, ! PrimeQ@ #]] &] ] (* Michael De Vlieger, Aug 01 2017, after Fred Daniel Kline at A045948 *)

Python

# uses program from A025476
from math import prod
def A048148(n): return prod(A025476(i) for i in range(1,n)) # Chai Wah Wu, Aug 15 2024

Formula

A025476(n) = a(n+1) / a(n). - Eric Desbiaux, Jun 22 2013

Extensions

More terms from James Sellers, May 03 2000

More terms from Michael De Vlieger, Aug 01 2017