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A272177 Alternating row sum of row 2n in A238453. 0
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 (list; graph; refs; listen; history; text; internal format)
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: A033936 A203618 A098814 * A156437 A127071 A151333

Adjacent sequences:  A272174 A272175 A272176 * A272178 A272179 A272180

KEYWORD

nonn

AUTHOR

Tom Edgar, Apr 21 2016

STATUS

approved

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Last modified October 22 00:52 EDT 2019. Contains 328315 sequences. (Running on oeis4.)