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A363854 Number of divisors of 7*n-2 of form 7*k+6. 5
0, 1, 0, 1, 0, 1, 0, 2, 0, 1, 0, 1, 0, 2, 0, 1, 1, 1, 0, 2, 0, 1, 0, 1, 0, 3, 0, 1, 0, 2, 0, 2, 0, 1, 1, 1, 0, 2, 0, 1, 0, 1, 1, 3, 0, 2, 0, 1, 0, 2, 0, 1, 1, 1, 0, 3, 0, 1, 0, 1, 0, 4, 0, 1, 0, 2, 0, 2, 1, 1, 1, 1, 0, 2, 0, 1, 0, 2, 0, 3, 0, 2, 0, 1, 0, 3, 0, 1, 2, 1, 0, 2, 0, 2, 1, 1, 0, 3, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,8
COMMENTS
Also number of divisors of 7*n-2 of form 7*k+2.
LINKS
Table of n, a(n) for n=1..100.
FORMULA
a(n) = A363795(7*n-2) = A363808(7*n-2).
G.f.: Sum_{k>0} x^(2*k)/(1 - x^(7*k-1)).
G.f.: Sum_{k>0} x^(6*k-4)/(1 - x^(7*k-5)).
MATHEMATICA
a[n_] := DivisorSum[7*n - 2, 1 &, Mod[#, 7] == 6 &]; Array[a, 100] (* Amiram Eldar, Jun 25 2023 *)
PROG
(PARI) a(n) = sumdiv(7*n-2, d, d%7==6);
CROSSREFS
Cf. A361691, A363855, A363856, A363857, A363858.
Cf. A363795, A363808.
Sequence in context: A178111 A178112 A324852 * A353967 A035169 A340728
Adjacent sequences: A363851 A363852 A363853 * A363855 A363856 A363857
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jun 24 2023
STATUS
approved

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Last modified August 30 07:09 EDT 2024. Contains 375532 sequences. (Running on oeis4.)