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A272178
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Absolute value of alternating row sum of row 2n in A238498.
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0
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1, 1, 2, 10, 54, 322, 1294, 4526, 20782, 93814, 371110, 1780294, 6733918, 22513642, 92018398, 461754862, 1297077342, 5790726826, 32850248974, 94597335398, 454725608974, 2080853077822, 6173935052878, 29922219241486, 116844904688830, 448338212337298, 1975870364475334
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OFFSET
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0,3
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COMMENTS
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The alternating row sums of the odd-indexed rows are 0.
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LINKS
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FORMULA
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For n>0, a(n) = Sum_{k=0..2n}(-1)^(k+1)*A238498(2n,k).
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PROG
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(Sage)
P=[0]+[i*prod([(1+1/x) for x in prime_divisors(i)]) for i in [1..100]]
Tr=[[prod(P[1:n+1])/(prod(P[1:k+1])*prod(P[1:(n-k)+1])) for k in [0..n]] for n in [0..len(P)-1]]
L=[sum((-1)^(i)*x[i] for i in [0..len(x)-1]) for x in Tr]
[abs(y) for y in L if y!=0]
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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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