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A113303 Least number k such that prime(n) divides T(k), the central trinomial coefficient A002426(k), or 0 if there is no such k. 5
0, 2, 0, 3, 0, 0, 5, 4, 0, 0, 0, 0, 8, 9, 6, 0, 0, 0, 0, 0, 9, 0, 0, 0, 0, 0, 0, 26, 47, 12, 0, 7, 0, 0, 0, 0, 0, 0, 0, 28, 44, 0, 31, 51, 0, 61, 0, 0, 0, 0, 27, 0, 0, 0, 0, 0, 89, 0, 90, 135, 98, 48, 122, 120, 0, 0, 0, 0, 121, 0, 0, 0, 0, 112, 0, 91, 0, 0, 55, 63, 133, 48, 0, 0, 126, 179, 0, 78 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
When a(n)=0, prime(n) is in A113305. When a(n)>0, prime(n) is in A113304.
LINKS
MATHEMATICA
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]; k=1; While[k<nn && Mod[t[[k]], p]>0, k++ ]; If[k==nn, 0, k], {i, PrimePi[nn]}]
CROSSREFS
Cf. A113302 (number of k for which prime(n) divides T(k)).
Sequence in context: A071391 A102390 A127640 * A080089 A322841 A291044
KEYWORD
nonn
AUTHOR
T. D. Noe, Oct 24 2005
STATUS
approved

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Last modified April 24 06:03 EDT 2024. Contains 371918 sequences. (Running on oeis4.)