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 A177055 Numbers k such that each decimal digit is a quadratic non-residue modulo k. 1
 22, 25, 26, 32, 35, 36, 38, 52, 53, 56, 63, 65, 66, 72, 75, 76, 77, 78, 85, 88, 222, 225, 228, 232, 235, 236, 237, 252, 255, 256, 258, 262, 266, 267, 268, 272, 273, 275, 276, 282, 283, 285, 286, 288, 323, 325, 332, 333, 335, 336, 352, 353, 357, 368, 372, 375, 376, 377, 385, 387, 522, 523, 525, 528, 532, 533, 535, 536 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The digits 0,1,4,9 are squares, so no members of the sequence have those digits. - Robert Israel, Apr 03 2017 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE 75 is in the sequence because neither 7 nor 5 is a square mod 75. - Corrected by Robert Israel, Apr 03 2017 MAPLE isA177055 := proc(n) local d; for d in convert(n, base, 10) do if numtheory[quadres](d, n) <> -1 then return false; end if; end do; return true; end proc: for n from 1 to 140 do if isA177055(n) then printf("%d, ", n) ; end if ; end do: # R. J. Mathar, Dec 12 2010 CROSSREFS Sequence in context: A061411 A053779 A177734 * A186780 A034304 A167459 Adjacent sequences:  A177052 A177053 A177054 * A177056 A177057 A177058 KEYWORD nonn,base,less AUTHOR Michel Lagneau, Dec 09 2010 STATUS approved

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Last modified November 24 18:11 EST 2020. Contains 338616 sequences. (Running on oeis4.)