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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

Index entries for sequences related to factorial numbers

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

Jeff Burch

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.)