A062101 Squarefree numbers with every digit a squarefree number.

1, 2, 3, 5, 6, 7, 11, 13, 15, 17, 21, 22, 23, 26, 31, 33, 35, 37, 51, 53, 55, 57, 61, 62, 65, 66, 67, 71, 73, 77, 111, 113, 115, 122, 123, 127, 131, 133, 137, 151, 155, 157, 161, 163, 165, 166, 167, 173, 177, 211, 213, 215, 217, 221, 222, 223, 226, 227, 231, 233

Offset

1,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..5000

Example

a(9) = 15 is a squarefree number, 1 and 5 are also squarefree numbers.

Mathematica

With[{sf={1, 2, 3, 5, 6, 7}}, Flatten[Table[Select[FromDigits/@ Tuples[ sf, n], SquareFreeQ], {n, 3}]]]  (* Harvey P. Dale, Aug 09 2014 *)

Crossrefs

Sequence in context: A359397 A098962 A073485 * A330597 A352336 A283599

Adjacent sequences: A062098 A062099 A062100 * A062102 A062103 A062104

Keyword

nonn,base,easy

Author

Amarnath Murthy, Jun 16 2001

Extensions

More terms from Reiner Martin, Jul 20 2001

Status

approved