%I A113302
%S A113302 0,1,0,1,0,0,2,2,0,0,0,0,4,2,3,0,0,0,0,0,6,0,0,0,0,0,0,2,2,2,0,2,0,0,0,
%T A113302 0,0,0,0,2,2,0,3,4,0,2,0,0,0,0,6,0,0,0,0,0,2,0,2,2,2,2,2,2,0,0,0,0,2,0,
%U A113302 0,0,0,2,0,3,0,0,4,2,2,4,0,0,3,2,0,2,0,0,2,0,0,0,0,6,2,2,0,0,2,0,4,2,0
%N A113302 Number of k such that prime(n) divides T(k), the central trinomial coefficient
A002426(k), with 0<k<prime(n).
%C A113302 For primes less than 10^6, a(n) <= 10. Is 10 the largest possible value?
When a(n)=0, prime(n) is in A113305. When a(n)>0, prime(n) is in
A113304.
%t A113302 nn=1000; a=b=1; t=Join[{1}, Table[c=((2n-1)b+3(n-1)a)/n; a=b; b=c; c,
{n, 2, nn}]]; Table[p=Prime[i]; cnt=0; Do[If[Mod[t[[j]], p]==0, cnt++
], {j, p}]; cnt, {i, PrimePi[nn]}]
%Y A113302 Cf. A113303 (least k such that prime(n) divides T(k)).
%Y A113302 Sequence in context: A035447 A037863 A163536 this_sequence A049800 A131018
A035395
%Y A113302 Adjacent sequences: A113299 A113300 A113301 this_sequence A113303 A113304
A113305
%K A113302 nonn
%O A113302 1,7
%A A113302 T. D. Noe (noe(AT)sspectra.com), Oct 24 2005
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