A062084 Squarefree numbers such that every digit as well as sum of the digits is a squarefree number.

1, 2, 3, 5, 6, 7, 11, 15, 21, 23, 33, 37, 51, 55, 61, 65, 67, 73, 77, 111, 113, 115, 122, 123, 127, 131, 133, 137, 151, 155, 157, 163, 166, 167, 173, 177, 213, 217, 221, 222, 223, 226, 227, 231, 235, 253, 257, 262, 263, 265, 266, 267, 271, 311, 313, 317, 321

Offset

1,2

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

a(7) = 23 is a squarefree number, 2 and 3 are squarefree numbers and the sum of the digits 5 is also a squarefree number.

Mathematica

asfQ[n_]:=AllTrue[Flatten[{n, IntegerDigits[n], Total[IntegerDigits[ n]]}], SquareFreeQ]; Select[Range[350], asfQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 14 2021 *)

Crossrefs

Sequence in context: A023798 A369635 A362455 * A331394 A273524 A098959

Adjacent sequences: A062081 A062082 A062083 * A062085 A062086 A062087

Keyword

nonn,base,easy

Author

Amarnath Murthy, Jun 16 2001

Extensions

Corrected and extended by Larry Reeves (larryr(AT)acm.org), Jun 19 2001

Status

approved