OFFSET
1,1
MATHEMATICA
Array[4^#*(1 - 4^#) BernoulliB[2 #]/(2 #) + EulerE[2 #] &, 16] (* Michael De Vlieger, May 24 2018 *)
PROG
(PARI) a(n) = 4^n * (1 - 4^n) * bernfrac(2*n) / (2*n) + 2*imag(polylog(-2*n, I)); \\ Michel Marcus, May 30 2018
CROSSREFS
KEYWORD
sign
AUTHOR
Daniel Suteu, May 22 2018
STATUS
approved