A071592 Numbers m such that Reversal(m) is not squarefree.

4, 8, 9, 18, 21, 23, 25, 27, 29, 36, 40, 42, 44, 45, 46, 48, 52, 54, 57, 61, 63, 65, 67, 69, 72, 80, 81, 82, 84, 86, 88, 89, 90, 94, 99, 108, 117, 121, 126, 135, 139, 144, 148, 153, 162, 163, 169, 171, 180, 189, 198, 207, 210, 211, 212, 213, 214, 215, 216, 217, 218

Offset

1,1

Links

Table of n, a(n) for n=1..61.

Mathematica

Select[Range[218], !SquareFreeQ[FromDigits[Reverse[IntegerDigits[#]]]] &] (* Stefano Spezia, Jun 27 2025 *)

Prog

(PARI) isok(m) = !issquarefree(fromdigits(Vecrev(digits(m)))); \\ Michel Marcus, Feb 16 2021

Crossrefs

Cf. A004086, A013929.

Complement of A071591.

Sequence in context: A162898 A385351 A257009 * A089765 A116030 A116020

Adjacent sequences: A071589 A071590 A071591 * A071593 A071594 A071595

Keyword

base,easy,nonn

Author

Benoit Cloitre, Jun 01 2002

Status

approved