Let c = composite(n) & p = prime(n); a(n) = binomial( max(c,p), min(c,p) ).

A109903

Let c = composite(n) & p = prime(n); a(n) = binomial( max(c,p), min(c,p) ).

Terms

    a(0) =6a(1) =20a(2) =56a(3) =36a(4) =11a(5) =13a(6) =680a(7) =3876a(8) =245157a(9) =34597290a(10) =84672315a(11) =12875774670a(12) =244662670200a(13) =800472431850

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