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A346389
a(n) is the number of proper divisors of A324297(n) ending with 6.
5
1, 2, 2, 2, 1, 2, 3, 3, 2, 2, 2, 4, 2, 1, 2, 2, 3, 3, 2, 2, 4, 2, 5, 3, 3, 2, 2, 2, 4, 2, 2, 2, 3, 3, 4, 3, 4, 2, 5, 3, 3, 2, 2, 2, 2, 7, 2, 1, 2, 2, 3, 2, 3, 2, 2, 5, 3, 6, 3, 3, 2, 2, 2, 5, 2, 2, 3, 4, 3, 5, 2, 5, 4, 3, 2, 3, 6, 2, 2, 2, 6, 2, 2, 3, 2, 2, 3, 7
OFFSET
1,2
FORMULA
a(n) = A346392(A324297(n)).
EXAMPLE
a(12) = 4 since there are 4 proper divisors of A324297(12) = 576 ending with 6: 6, 16, 36 and 96.
MATHEMATICA
b={}; For[n=0, n<=450, n++, For[k=0, k<=n, k++, If[Mod[10*n+6, 10*k+6]==0 && Mod[(10*n+6)/(10*k+6), 10]==6 && 10*n+6>Max[b], AppendTo[b, 10*n+6]]]]; (* A324297 *) a={}; For[i =1, i<=Length[b], i++, AppendTo[a, Length[Drop[Select[Divisors[Part[b, i]], (Mod[#, 10]==6&)], -1]]]]; a
CROSSREFS
Cf. A017341, A032741, A324297, A324298, A337856, A346388 (ending with 5), A346392.
Sequence in context: A209323 A083647 A364332 * A056691 A262982 A205011
KEYWORD
nonn,base
AUTHOR
Stefano Spezia, Jul 15 2021
STATUS
approved