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 A066159 Numbers n such that 4n-1 divides (2n-1)! + 1. 2
 2, 3, 5, 11, 12, 17, 20, 26, 32, 33, 41, 45, 48, 50, 57, 66, 87, 92, 96, 105, 108, 111, 120, 123, 126, 131, 141, 143, 150, 152, 155, 158, 171, 173, 182, 185, 186, 197, 206, 210, 216, 222, 237, 248, 255, 263, 272, 273, 281, 288, 297, 323, 330, 342 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Harry J. Smith, Table of n, a(n) for n=1..1000 Ed Pegg, Jr., Math. Puzzles (Material added Dec 11 2001) MAPLE A066159:=n->`if`((2*n-1)!+1 mod (4*n-1) = 0, n, NULL): seq(A066159(n), n=1..500); # Wesley Ivan Hurt, Dec 01 2015 MATHEMATICA Select[Range@ 360, Divisible[(2 # - 1)! + 1, 4 # - 1] &] (* Michael De Vlieger, Dec 02 2015 *) PROG (PARI) { n=0; for (m=1, 10^9, if (frac(((2*m - 1)! + 1)/(4*m - 1)) == 0, write("b066159.txt", n++, " ", m); if (n==1000, return)) ) } \\ Harry J. Smith, Feb 03 2010 CROSSREFS Cf. A066160. Sequence in context: A259155 A210144 A243357 * A316794 A103027 A093902 Adjacent sequences:  A066156 A066157 A066158 * A066160 A066161 A066162 KEYWORD nonn AUTHOR N. J. A. Sloane, Dec 13 2001 EXTENSIONS Reference into the Math Puzzles made more specific by R. J. Mathar, Feb 11 2010 STATUS approved

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Last modified October 29 07:37 EDT 2020. Contains 338066 sequences. (Running on oeis4.)