A272177 Alternating row sum of row 2n in A238453.

1, 1, 2, 6, 42, 162, 634, 2726, 9330, 37814, 186034, 623934, 2370354, 10505738, 37417658, 113248562, 738713250, 2753640290, 7522970666, 46292418830, 146514514914, 496491671978, 2915741154442, 9464309679414, 39098814277474, 173211426442282, 652232674100690

Offset

0,3

Comments

The alternating row sums of odd rows in A238453 are 0.

Links

Table of n, a(n) for n=0..26.

Tom Edgar, Totienomial Coefficients, INTEGERS, 14 (2014), #A62.

Formula

a(n) = Sum_{k=0..2n}(-1)^k*A238453(2n,k).

Prog

P=[euler_phi(i) for i in [0..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]
print [y for y in L if y!=0]

Crossrefs

Cf. A000010, A238453, A272079.

Sequence in context: A203618 A334883 A098814 * A346548 A321250 A156437

Adjacent sequences: A272174 A272175 A272176 * A272178 A272179 A272180

Keyword

nonn

Author

Tom Edgar, Apr 21 2016

Status

approved