A226796 Number of nonnegative numbers x < 10^n such that the digits of x^2 occur with an equal frequency of 1.

10, 59, 221, 441, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611, 611

Offset

1,1

Links

Table of n, a(n) for n=1..52.

Example

All numbers 0 to 9 have squares containing only digits of frequency 1: 0, 1, 4, 9, 16, 25, 36, 49, 64, 81. See A119509 for the positive terms.

Mathematica

cnt = 0; x = 0; Table[While[x < 10^n, If[Union[Last[Transpose[Tally[IntegerDigits[x^2]]]]] == {1}, cnt++]; x++]; cnt, {n, 5}]

Crossrefs

Cf. A119509 (positive terms x), A225428 (for 2 digits).

Sequence in context: A044529 A129330 A045950 * A061001 A055586 A326827

Adjacent sequences: A226793 A226794 A226795 * A226797 A226798 A226799

Keyword

nonn,base

Author

T. D. Noe, Jun 21 2013

Status

approved