A054032 - OEIS

A054032

Numbers n such that n^2 contains exactly 4 different digits.

32, 33, 36, 37, 42, 43, 44, 48, 49, 51, 52, 53, 54, 55, 57, 59, 61, 64, 66, 69, 71, 72, 73, 74, 78, 79, 82, 84, 86, 87, 89, 93, 95, 96, 98, 99, 103, 104, 105, 106, 112, 114, 115, 123, 125, 127, 130, 132, 135, 138, 139, 140, 143, 145, 146, 151, 155, 156, 157, 158

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

T. D. Noe, Table of n, a(n) for n = 1..10000

MAPLE

f := []; for i from 0 to 200 do if nops({op(convert(i^2, base, 10))})=4 then f := [op(f), i] fi; od; f;

MATHEMATICA

t = {}; n = -1; While[Length[t] < 50, n++; If[Length[Union[IntegerDigits[n^2]]] == 4, AppendTo[t, n]]] (* T. D. Noe, Apr 26 2013 *)

PROG

(PARI) is(n)=#Set(digits(n^2))==4 \\ Charles R Greathouse IV, Feb 11 2017

CROSSREFS