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 A272178 Absolute value of alternating row sum of row 2n in A238498. 0
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS The alternating row sums of the odd-indexed rows are 0. LINKS Table of n, a(n) for n=0..26. Tom Edgar, Totienomial Coefficients, INTEGERS, 14 (2014), #A62. FORMULA For n>0, a(n) = Sum_{k=0..2n}(-1)^(k+1)*A238498(2n,k). PROG (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] CROSSREFS Cf. A001615, A238498, A272080. Sequence in context: A102536 A221604 A163909 * A152395 A365879 A202365 Adjacent sequences: A272175 A272176 A272177 * A272179 A272180 A272181 KEYWORD nonn AUTHOR Tom Edgar, Apr 21 2016 STATUS approved

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Last modified December 8 08:50 EST 2023. Contains 367663 sequences. (Running on oeis4.)