A248136 Least positive integer m such that m + n divides D(m) + D(n), where D(.) is given by A001850.
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
Keywords
Examples
a(2) = 20 since 2 + 20 = 22 divides D(2) + D(20) = 13 + 260543813797441 = 260543813797454 = 22*11842900627157.
Links
- Zhi-Wei Sun, Table of n, a(n) for n = 1..10000
Crossrefs
Programs
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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}]
Comments