A337373 Numbers k for which A003961(k) > 3*k.

8, 12, 16, 18, 20, 24, 27, 28, 30, 32, 36, 40, 42, 45, 48, 54, 56, 60, 63, 64, 70, 72, 75, 78, 80, 81, 84, 88, 90, 96, 98, 99, 100, 104, 105, 108, 112, 114, 117, 120, 126, 128, 132, 135, 136, 138, 140, 144, 147, 150, 152, 153, 156, 160, 162, 168, 171, 175, 176, 180, 182, 184, 189, 192, 195, 196, 198, 200, 204, 207, 208

Offset: 1

Author

Antti Karttunen, Aug 26 2020

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..10000
• Index entries for sequences computed from indices in prime factorization

Crossrefs

Cf. A003961.

Subsequence of A246282.

Cf. A337374 (a subsequence).

Programs

Maple

filter:= proc(n) local F,t;
  F:= ifactors(n)[2];
  mul((nextprime(t[1])/t[1])^t[2], t=F) > 3
end proc:
select(filter, [$1..1000]); # Robert Israel, Dec 31 2023

PARI

A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
isA337373(n) = (A003961(n) > (3*n));