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A318660
Remainder when A064988(n) is divided by n.
2
0, 1, 2, 1, 1, 3, 3, 3, 7, 3, 9, 9, 2, 9, 10, 1, 8, 3, 10, 19, 1, 5, 14, 15, 21, 19, 17, 13, 22, 15, 3, 19, 23, 7, 12, 9, 9, 11, 10, 17, 15, 3, 19, 15, 5, 19, 23, 21, 44, 13, 40, 5, 29, 51, 11, 11, 50, 37, 41, 15, 39, 9, 47, 25, 61, 3, 63, 55, 1, 1, 69, 27, 2, 27, 5, 71, 65, 69, 6, 11, 58, 45, 16, 9, 54, 57, 23, 45, 16, 15, 60, 11, 77, 69
OFFSET
1,3
COMMENTS
Inspired by A064988 and a 'minimum' version of it (A318871).
a(n) = 0 only for n = 1. Numbers n such that a(n) = 1 are 2, 4, 5, 16, 21, 69, 70, 181, 265, 370, 1043, 3760, 4531, ...
LINKS
FORMULA
a(n) = A064988(n) mod n.
a(A000040(n)) = A076240(n).
EXAMPLE
a(6) = prime(2)*prime(3) mod 6 = 15 mod 6 = 3.
MATHEMATICA
Table[Mod[If[n == 1, 1, Apply[Times, FactorInteger[n] /. {p_, e_} /; p > 1 :> Prime[p]^e]], n], {n, 94}] (* Michael De Vlieger, Sep 10 2018 *)
PROG
(PARI) A318660(n) = { my(f = factor(n)); for (k=1, #f~, f[k, 1] = prime(f[k, 1]); ); (factorback(f)%n); }; \\ After code in A064988.
CROSSREFS
KEYWORD
nonn
AUTHOR
Altug Alkan and Antti Karttunen, Sep 08 2018
STATUS
approved