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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
OFFSET
0,3
COMMENTS
The alternating row sums of odd rows in A238453 are 0.
LINKS
Tom Edgar, Totienomial Coefficients, INTEGERS, 14 (2014), #A62.
FORMULA
a(n) = Sum_{k=0..2n}(-1)^k*A238453(2n,k).
PROG
(Sage)
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
KEYWORD
nonn
AUTHOR
Tom Edgar, Apr 21 2016
STATUS
approved