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A198863 Numbers such that their squares are pandigital numbers with exactly two occurrences of each digit. 0
3164252736, 3164326683, 3164389113, 3164391957, 3164406057, 3164416923, 3164421333, 3164454864, 3164466768, 3164482974, 3164528124, 3164547114, 3164689392, 3164695206, 3164735277, 3164770866, 3164789766, 3164863185, 3164867118, 3164907357, 3165009693 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Later terms include: 4000171725, 4000183233, 4000198443, 4000203567.

Because the sum of the digits of n^2 is 90, 9 divides n^2. Hence, 3 divides n. - T. D. Noe, Nov 08 2011

LINKS

Table of n, a(n) for n=1..21.

EXAMPLE

4000171725^2 = 16001373829489475625.

MATHEMATICA

Select[Range[3164250000, 3164450000], Union[DigitCount[#^2]] == {2} &] (* Alonso del Arte, Oct 31 2011 *)

t = {}; n = 3164211348; nMax = 9994386752; While[n <= nMax && Length[t] < 21, While[n <= nMax && Union[DigitCount[n^2]] != {2}, n = n + 3]; If[n <= nMax, AppendTo[t, n]; Print[n]; n = n + 3]]; t (* T. D. Noe, Nov 08 2011 *)

CROSSREFS

Cf. A156977 (n^2 contains each digit once).

Sequence in context: A092380 A096566 A217051 * A199630 A198298 A074773

Adjacent sequences:  A198860 A198861 A198862 * A198864 A198865 A198866

KEYWORD

nonn,base,fini

AUTHOR

Pablo Martínez, Oct 30 2011

EXTENSIONS

All displayed terms are from Charles R Greathouse IV, Alonso del Arte and T. D. Noe, Nov 08 2011

STATUS

approved

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Last modified February 22 12:33 EST 2020. Contains 332136 sequences. (Running on oeis4.)