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A248136
Least positive integer m such that m + n divides D(m) + D(n), where D(.) is given by A001850.
6
1, 20, 3, 6, 1, 4, 200, 299, 5, 29, 4, 119, 5, 61, 3, 3, 6, 64, 31, 2, 21, 35, 6, 2974, 17, 1052, 27, 109, 10, 4, 3, 50, 65, 177, 22, 29, 5, 25, 15, 29, 29, 584, 83, 163, 9, 152, 19, 19, 29, 32, 15, 35, 4, 25, 239, 1122, 185, 76, 35, 97
OFFSET
1,2
COMMENTS
Conjecture: a(n) exists for any n > 0.
EXAMPLE
a(2) = 20 since 2 + 20 = 22 divides D(2) + D(20) = 13 + 260543813797441 = 260543813797454 = 22*11842900627157.
MATHEMATICA
d[n_]:=Sum[Binomial[n, k]Binomial[n+k, k], {k, 0, n}]
Do[m=1; Label[aa]; If[Mod[d[m]+d[n], m+n]==0, Print[n, " ", m]; Goto[bb]]; m=m+1; Goto[aa]; Label[bb]; Continue, {n, 1, 60}]
KEYWORD
nonn
AUTHOR
Zhi-Wei Sun, Oct 02 2014
STATUS
approved