%I A109903
%S A109903 6,20,56,36,11,13,680,3876,245157,34597290,84672315,12875774670,
%T A109903 244662670200,800472431850,14833897694226,973469712824056,
%U A109903 48402641245296107,191724747789809255,9989690752182277136
%N A109903 Let c = composite(n) & p = prime(n); a(n) = binomial( max(c,p), min(c,
p) ).
%C A109903 11 and 13 are the only prime terms. For a(7) onwards sequence is monotonically
increasing.
%e A109903 a(3) = C(8,5) = 56, a(8) = C(19,15) =3876.
%t A109903 Composite[ n_Integer ] := Block[{k = n + PrimePi[ n ] + 1}, While[ k
!= n + PrimePi[ k ] + 1, k++ ]; k]; f[n_] := Block[{a = Sort[{Composite[n],
Prime[n]}]}, Binomial[Last[a], First[a]]]; Table[ f[n], {n, 19}]
(from Robert G. Wilson v (rgwv(at)rgwv.com), Jul 16 2005)
%Y A109903 Sequence in context: A028492 A059822 A152959 this_sequence A014480 A048778
A048611
%Y A109903 Adjacent sequences: A109900 A109901 A109902 this_sequence A109904 A109905
A109906
%K A109903 easy,nonn
%O A109903 1,1
%A A109903 Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jul 14 2005
%E A109903 More terms from Robert G. Wilson v (rgwv(at)rgwv.com), Jul 16 2005
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