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A324438
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a(n) = Product_{i=1..n, j=1..n} (i^5 + j^5).
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9
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) ~ c * 2^(2*n*(n+1)) * phi^(sqrt(5)*n*(n+1)) * exp(Pi*sqrt(phi)*n*(n+1)/5^(1/4) - 15*n^2/2) * n^(5*n^2 - 5/4), where phi = A001622 = (1+sqrt(5))/2 is the golden ratio and c = 0.1574073828647726237455544898360432469056972905505624900871695...
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MAPLE
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a:= n-> mul(mul(i^5 + j^5, i=1..n), j=1..n):
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MATHEMATICA
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Table[Product[i^5 + j^5, {i, 1, n}, {j, 1, n}], {n, 1, 6}]
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PROG
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(Python)
from math import prod, factorial
def A324438(n): return prod(i**5+j**5 for i in range(1, n) for j in range(i+1, n+1))**2*factorial(n)**5<<n # Chai Wah Wu, Nov 26 2023
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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