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
Keywords
Links
- Tom Edgar, Totienomial Coefficients, INTEGERS, 14 (2014), #A62.
Programs
-
Sage
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]
Formula
For n>0, a(n) = Sum_{k=0..2n}(-1)^(k+1)*A238498(2n,k).
Comments