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A071129 Squares which repeat with at least two full periods when written in base 3. 2
4, 121, 841, 6889, 60025, 62001, 68644, 534361, 540225, 1042441, 4791721, 4809249, 20811844, 43072969, 43125489, 43283241, 387499225, 387656721, 388129401, 567725929, 713584369, 1255284900, 2231617600, 3487020601, 3487493025, 3488910489, 31381768201 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..131 (terms < 3^45)

EXAMPLE

11^2 = 121 = 1|1|1|1|1 in base 3.

249^2 = 62001 = 1001|1001|100 in base 3.

MATHEMATICA

psq[b_, nd_] := Block[{sq={}, r, x}, Do[r = Mod[nd, p]; Do[x = (b^( Floor[nd/p] p) - 1)/(b^p - 1) t  b^r + Floor[t/b^(p - r)]; If[ IntegerQ@ Sqrt@ x, AppendTo[ sq, x]], {t, b^(p - 1), b^p - 1}], {p, nd/2}]; sq]; Union @@ (psq[3, #] & /@ Range[20]) (* Giovanni Resta, Aug 01 2018 *)

CROSSREFS

Cf. A071128 (base 2) - A071135 (base 9), A069919 (base 10).

Sequence in context: A017186 A098839 A227525 * A241366 A263612 A033934

Adjacent sequences:  A071126 A071127 A071128 * A071130 A071131 A071132

KEYWORD

base,nonn

AUTHOR

Erich Friedman, May 28 2002

EXTENSIONS

a(25)-a(27) from Giovanni Resta, Aug 01 2018

STATUS

approved

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Last modified October 22 22:35 EDT 2021. Contains 348180 sequences. (Running on oeis4.)