A031162 Numbers that are both lucky and square.

1, 9, 25, 49, 169, 289, 361, 529, 729, 841, 961, 1369, 2209, 3481, 3721, 3969, 4761, 5041, 7921, 9409, 9801, 10609, 12321, 15129, 17689, 20449, 21609, 24025, 24649, 32041, 32761, 35721, 36481, 42025, 42849, 43681, 50625, 52441, 53361

Offset: 1

Author

Patrick De Geest

Keywords

• nonn

Links

• Donovan Johnson, Table of n, a(n) for n = 1..2512 (terms < 10^9)

Crossrefs

Cf. A000959, A031163.

Programs

Mathematica

lst = Range[1, 73440, 2]; i = 2; While[ i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++ ]; Select[lst, IntegerQ@ Sqrt@# &] (* Robert G. Wilson v, May 12 2006 *)