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 A045521 n! has initial digit '2'. 18
 2, 4, 16, 20, 23, 30, 32, 34, 39, 44, 47, 54, 58, 68, 75, 85, 86, 87, 113, 114, 115, 126, 135, 142, 148, 153, 159, 163, 168, 172, 180, 184, 188, 195, 205, 208, 211, 214, 217, 220, 223, 226, 234, 237, 242, 247, 252, 257, 262, 269, 276, 278, 287, 289, 302, 304 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Chai Wah Wu, Table of n, a(n) for n = 1..10000 MATHEMATICA Select[ Range[ 310 ], IntegerDigits[ #! ] [ [ 1 ] ] == 2 & ] PROG (PARI) isok(n) = digits(n!)[1] == 2; \\ Michel Marcus, Feb 07 2017 CROSSREFS For factorials with initial digit d (1 <= d <= 9) see A045509, A045510, A045511, A045516, A045517, A045518, A282021, A045519; A045520, A045521, A045522, A045523, A045524, A045525, A045526, A045527, A045528, A045529. See also A000142. Sequence in context: A229238 A212202 A102545 * A242205 A076434 A192150 Adjacent sequences:  A045518 A045519 A045520 * A045522 A045523 A045524 KEYWORD nonn,base AUTHOR EXTENSIONS Offset changed to 1 by Chai Wah Wu, Feb 07 2017 STATUS approved

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Last modified October 21 08:27 EDT 2018. Contains 316405 sequences. (Running on oeis4.)