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 A074944 Number of k with 1 <= k <= n such that gcd(n,k)=tau(k), where tau is A000005, number of divisors function. 1
 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 4, 1, 2, 2, 2, 1, 3, 1, 3, 2, 2, 1, 4, 1, 2, 1, 3, 1, 5, 1, 3, 2, 2, 1, 3, 1, 2, 2, 3, 1, 5, 1, 3, 2, 2, 1, 5, 1, 2, 2, 3, 1, 3, 1, 4, 2, 2, 1, 5, 1, 2, 2, 5, 1, 5, 1, 3, 2, 2, 1, 5, 1, 2, 2, 3, 1, 5, 1, 4, 2, 2, 1, 7, 1, 2, 2, 5, 1, 4, 1, 3, 2, 2, 1, 9, 1, 2, 2, 3, 1, 5, 1, 6, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Antti Karttunen, Table of n, a(n) for n = 1..16384 FORMULA Sum_{i=1..n} a(i) seems to be asymptotic to c*n*log(n) with 0.5 < c < 0.6. PROG (PARI) a(n)=sum(k=1, n, if(gcd(n, k)-numdiv(k), 0, 1)) CROSSREFS Cf. A000005. Sequence in context: A161288 A185217 A131456 * A245041 A161315 A161249 Adjacent sequences:  A074941 A074942 A074943 * A074945 A074946 A074947 KEYWORD easy,nonn AUTHOR Benoit Cloitre, Oct 05 2002 STATUS approved

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Last modified October 20 20:24 EDT 2019. Contains 328273 sequences. (Running on oeis4.)