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A226797 Number of n-digit numbers x such that the digits of x^2 occur with frequency 1. 0
10, 49, 162, 220, 170, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

After a(5), all terms are 0.

LINKS

Table of n, a(n) for n=1..85.

EXAMPLE

All numbers 0 to 9 have squares containing only digits of frequency 1: 0, 1, 4, 9, 16, 25, 36, 49, 64, 81.

MATHEMATICA

cnt = 0; x = 0; t2 = Table[While[x < 10^n, If[Union[Last[Transpose[Tally[IntegerDigits[x^2]]]]] == {1}, cnt++]; x++]; cnt, {n, 5}]; Differences[Join[{0}, t2]]

CROSSREFS

Cf. A225428, A226796.

Sequence in context: A154066 A056578 A307904 * A163716 A271662 A244864

Adjacent sequences: A226794 A226795 A226796 * A226798 A226799 A226800

KEYWORD

nonn,base

AUTHOR

T. D. Noe, Jun 21 2013

STATUS

approved

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Last modified December 8 01:00 EST 2022. Contains 358671 sequences. (Running on oeis4.)