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 A276000 Least k such that n! divides phi(k!) (k > 0). 1
 1, 3, 6, 6, 10, 10, 14, 14, 14, 14, 22, 22, 26, 26, 26, 26, 34, 34, 38, 38, 38, 38, 46, 46, 46, 46, 46, 46, 58, 58, 62, 62, 62, 62, 62, 62, 74, 74, 74, 74, 82, 82, 86, 86, 86, 86, 94, 94, 94, 94, 94, 94, 106, 106, 106, 106, 106, 106, 118, 118, 122, 122, 122, 122 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Robert Israel, Table of n, a(n) for n = 1..5000 FORMULA a(n) = 2*A007917(n) for n>2. - Andrey Zabolotskiy, Aug 16 2016 EXAMPLE a(2) = 3 because phi(3!) is divisible by 2!. MAPLE N:= 100: # for a(1)..a(N) V:= Vector(N): n:= 0: for k from 1 while n < N do   r:= numtheory:-phi(k!);   for i from n+1 to N while r mod (i!) = 0 do     V[i]:= k; n:= i;   od; od: convert(V, list); # Robert Israel, Apr 24 2020 MATHEMATICA Array[Block[{k = 1}, While[Mod[EulerPhi[k!], #!] != 0, k++]; k] &, 64] (* Michael De Vlieger, Apr 24 2020 *) PROG (PARI) a(n) = {my(k = 1); while(eulerphi(k!) % n!, k++); k; } CROSSREFS Cf. A048855, A007917. Sequence in context: A111652 A159787 A184161 * A333616 A316563 A349212 Adjacent sequences:  A275997 A275998 A275999 * A276001 A276002 A276003 KEYWORD nonn AUTHOR Altug Alkan, Aug 16 2016 STATUS approved

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Last modified May 27 11:47 EDT 2022. Contains 354097 sequences. (Running on oeis4.)