A071424 a(n) = a(n-1) + number of decimal digits of n!. Number of decimal digits of concatenation of first n factorials.

1, 2, 3, 5, 8, 11, 15, 20, 26, 33, 41, 50, 60, 71, 84, 98, 113, 129, 147, 166, 186, 208, 231, 255, 281, 308, 337, 367, 398, 431, 465, 501, 538, 577, 618, 660, 704, 749, 796, 844, 894, 946, 999, 1054, 1111, 1169, 1229, 1291, 1354, 1419, 1486, 1554, 1624

Offset

1,2

Links

Table of n, a(n) for n=1..53.

Mathematica

Do[s=s+Length[IntegerDigits[n! ]]; Print[s], {n, 1, 128}]

Crossrefs

Cf. A058183.

Sequence in context: A096777 A125811 A281706 * A008762 A308823 A363047

Adjacent sequences: A071421 A071422 A071423 * A071425 A071426 A071427

Keyword

easy,nonn,base

Author

Labos Elemer, May 27 2002

Status

approved