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A071134 Squares which repeat with at least two full periods when written in base 8. 2
9, 36, 6241, 116964, 418609, 28121809, 477247716, 1277991001, 1967188609, 5111964004, 7681646025, 73073443041, 79698371481, 91424593225, 120297291921, 292293772164, 318793485924, 1954689202404, 5429696889241, 5480313774049, 21718787556964, 21921255096196 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..57 (terms < 8^27)

EXAMPLE

647^2 = 418609 = 146|146|1 in base 8.

21846^2 = 477247716 = 34344|34344 in base 8.

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[8, #] & /@ Range[11]) (* Giovanni Resta, Aug 01 2018 *)

CROSSREFS

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

Sequence in context: A079655 A203764 A053949 * A116108 A232257 A091961

Adjacent sequences:  A071131 A071132 A071133 * A071135 A071136 A071137

KEYWORD

base,nonn

AUTHOR

Erich Friedman, May 28 2002

EXTENSIONS

Missing a(18) and more terms from Giovanni Resta, Aug 01 2018

STATUS

approved

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Last modified December 8 16:57 EST 2021. Contains 349596 sequences. (Running on oeis4.)