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 A069919 Squares which repeat with at least two full periods when written in base 10. 10
 69696, 56722567225, 95540955409, 1108033241108033241, 1220096161220096161, 4312080784312080784, 4432132964432132964, 4880384644880384644, 9024307889024307889, 9972299169972299169, 225607697225607697225, 946308825294630882529, 1322314049613223140496 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Giovanni Resta, Table of n, a(n) for n = 1..21 (terms < 10^24) EXAMPLE 264^2 = 69|69|6 in base 10. 15020242915^2 = 225607697|225607697|225 in base 10. 36363636364^2 = 13223140496|13223140496 in base 10. 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[10, #] & /@ Range[11]) (* Giovanni Resta, Aug 01 2018 *) CROSSREFS Cf. A071128 (base 2) - A071135 (base 9), A116502. Sequence in context: A224324 A053075 A154818 * A116502 A190934 A043600 Adjacent sequences: A069916 A069917 A069918 * A069920 A069921 A069922 KEYWORD base,nonn AUTHOR Erich Friedman, Apr 25 2002 EXTENSIONS Corrected and extended by Jason Earls, Jun 16 2002 Data corrected and extended by Giovanni Resta, Aug 01 2018 STATUS approved

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Last modified September 19 09:46 EDT 2024. Contains 376008 sequences. (Running on oeis4.)