A167761 a(n) = sqrt(A167657(n)).

0, 1, 2, 3, 16, 5, 36, 7, 64, 729, 10, 1331, 144, 13, 196, 3375, 4096, 17, 5832, 361, 20, 9261, 484, 12167, 331776, 625, 26, 729, 28, 841, 21870000000, 961, 32768, 33, 45435424, 35, 46656, 50653, 1444, 59319, 64000, 41, 130691232, 43, 1936, 45, 9474296896

Offset: 1

Author

Giovanni Teofilatto, Nov 11 2009, corrected Nov 12 2009

Keywords

• nonn

Comments

a(n) = prime => A096478(n).

If a(n) = prime => A096478(n). - Giovanni Teofilatto, Nov 12 2009

Crossrefs

Cf. A167657.

Cf. A096478. - Giovanni Teofilatto, Nov 12 2009

Programs

Maple

A000720 := proc(n) numtheory[pi](n) ; end proc: A167761 := proc(nmax) local ol,a ; ol := 0 ; a := 0 ; for n from 1 to nmax do if A000720(n) = ol then a := a*ol ; else printf("%d,",sqrt(a)) ; a := A000720(n) ; end if; ol := A000720(n) ; end do ; return ; end proc: A167761(260) ; # R. J. Mathar, Jan 30 2010

Extensions

Previous a(15) removed, a(35) and a(43) corrected by R. J. Mathar, Jan 30 2010

a(47) from Kritsada Moomuang, Apr 19 2025