A272178 Absolute value of alternating row sum of row 2n in A238498.

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

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

(SageMath)
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 A369263 A365879

Adjacent sequences: A272175 A272176 A272177 * A272179 A272180 A272181

Keyword

nonn

Author

Tom Edgar, Apr 21 2016

Status

approved