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A014348
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Three-fold exponential convolution of primes with themselves (divided by 2).
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1
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4, 18, 84, 393, 1830, 8433, 38376, 171957, 757362, 3271533, 13849980, 57396693, 233039058, 927277245, 3624209748, 13934877933, 52843565490, 197989340133, 734212702164, 2698456656933, 9837838481154, 35609804891973, 128026118332596, 457386991178451
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OFFSET
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0,1
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LINKS
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MAPLE
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b:= proc(n, k) option remember; `if`(k=1, ithprime(n+1), add(
b(j, floor(k/2))*b(n-j, ceil(k/2))*binomial(n, j), j=0..n))
end:
a:= n-> b(n, 3)/2:
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MATHEMATICA
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b[n_, k_] := b[n, k] = If[k==1, Prime[n+1], Sum[b[j, Floor[k/2]] b[n-j, Ceiling[k/2]] Binomial[n, j], {j, 0, n}]];
a[n_] := b[n, 3]/2;
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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