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A023672
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Convolution of A023533 and primes.
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1
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2, 3, 5, 9, 14, 18, 24, 30, 36, 48, 53, 65, 77, 85, 97, 111, 121, 131, 149, 163, 174, 192, 204, 220, 242, 260, 272, 294, 310, 320, 350, 364, 382, 410, 436, 453, 469, 495, 513, 543, 569, 587, 615, 647, 661, 687, 715, 739, 759, 799, 827, 855, 869
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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LINKS
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FORMULA
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a(n) = Sum_{j=1..n} A000040(k + binomial(n+3, 3) - binomial(j+2, 3)), for 1 <= k <= binomial(n+2, 2), n >= 1 (as an irregular triangle). - G. C. Greubel, Jul 18 2022
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MATHEMATICA
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A023672[n_, m_]:= A023672[n, m]= Sum[Prime[(m +Binomial[n+2, 3] -Binomial[j+2, 3])], {j, n}];
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PROG
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(Magma)
A023533:= func< n | Binomial(Floor((6*n-1)^(1/3)) +2, 3) ne n select 0 else 1 >;
(SageMath)
def A023672(n, k): return sum(nth_prime(k +binomial(n+2, 3) -binomial(j+2, 3)) for j in (1..n))
flatten([[A023672(n, k) for k in (1..binomial(n+2, 2))] for n in (1..10)]) # G. C. Greubel, Jul 18 2022
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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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