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 A048350 a(n)^2 is the smallest square containing exactly n 5's. 1
 5, 75, 235, 745, 22485, 22925, 235065, 505525, 2356384, 23569166, 227069495, 674919666, 3931354166, 7450205075, 39969432765, 524933839166, 2134374738666, 4904646324166, 23802428354166 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(20) > 10^14. - Giovanni Resta, Jul 27 2018 LINKS Eric Weisstein's World of Mathematics, Square Number MATHEMATICA k := 1; For[n = 1, n < 30000, n++, If[DigitCount[n^2][[5]] == k, k++; Print[n]]] (* Stefan Steinerberger, Apr 09 2006 *) a[n_] := Module[{i = 1}, While[DigitCount[i^2][[6]] != n, i++; ]; i]; (* Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 20 2006 *) CROSSREFS Cf. A036512, A034986, A048351. Sequence in context: A266570 A156703 A285452 * A030991 A216093 A151752 Adjacent sequences:  A048347 A048348 A048349 * A048351 A048352 A048353 KEYWORD nonn,base,more AUTHOR Patrick De Geest, Mar 15 1999 EXTENSIONS More terms from Jon E. Schoenfield, Jan 14 2009 One more term from Jon E. Schoenfield, Jan 25 2009 a(17)-a(19) from Giovanni Resta, Jul 27 2018 STATUS approved

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Last modified January 18 04:52 EST 2021. Contains 340250 sequences. (Running on oeis4.)