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Absolute value of alternating row sum of row 2n in A238498.
0

%I #11 Mar 15 2020 05:10:25

%S 1,1,2,10,54,322,1294,4526,20782,93814,371110,1780294,6733918,

%T 22513642,92018398,461754862,1297077342,5790726826,32850248974,

%U 94597335398,454725608974,2080853077822,6173935052878,29922219241486,116844904688830,448338212337298,1975870364475334

%N Absolute value of alternating row sum of row 2n in A238498.

%C The alternating row sums of the odd-indexed rows are 0.

%H Tom Edgar, <a href="http://www.emis.de/journals/INTEGERS/papers/o62/o62.Abstract.html">Totienomial Coefficients</a>, INTEGERS, 14 (2014), #A62.

%F For n>0, a(n) = Sum_{k=0..2n}(-1)^(k+1)*A238498(2n,k).

%o (Sage)

%o P=[0]+[i*prod([(1+1/x) for x in prime_divisors(i)]) for i in [1..100]]

%o 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]]

%o L=[sum((-1)^(i)*x[i] for i in [0..len(x)-1]) for x in Tr]

%o [abs(y) for y in L if y!=0]

%Y Cf. A001615, A238498, A272080.

%K nonn

%O 0,3

%A _Tom Edgar_, Apr 21 2016