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 A243293 Number of factorials < 10^n. 0
 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 14, 15, 16, 17, 18, 18, 19, 20, 21, 21, 22, 23, 24, 24, 25, 26, 26, 27, 28, 29, 29, 30, 31, 31, 32, 33, 33, 34, 34, 35, 36, 36, 37, 38, 38, 39, 40, 40, 41, 41, 42, 43, 43, 44, 44, 45, 46, 46, 47, 47, 48, 49, 49, 50, 50, 51, 52, 52, 53, 53 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A181590(150) does not agree with a(150). 0! and 1! are the same number so a(n) counts it as 1 number. LINKS EXAMPLE There are 4 factorials < 10^2: 0! = 1! = 1, 2! = 2, 3! = 6, and 4! = 24. Thus a(2) = 4. PROG (PARI) a(n) = {tot=0; for(k=1, 10^n, if(k!<10^n, tot++); if(k!>=10^n, break)); return(tot)} n=1; while(n<100, print1(a(n), ", "); n++) CROSSREFS Cf. A000142. Sequence in context: A260158 A317093 A181590 * A078923 A165240 A092460 Adjacent sequences:  A243290 A243291 A243292 * A243294 A243295 A243296 KEYWORD nonn AUTHOR Derek Orr, Jun 02 2014 STATUS approved

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Last modified February 16 15:17 EST 2020. Contains 331961 sequences. (Running on oeis4.)