A303394 Expansion of Product_{n>=1} ((1 - (4*x)^n)/(1 + (4*x)^n))^(1/4).

1, -2, -6, -28, -26, -156, -476, 968, 11526, -16172, 139724, 791928, 1315548, 12772840, 31004424, -105335920, 1058225606, 2239259700, -3700870212, 29301955992, -4944685836, -526686535112, 1134044530040, 4057865621232, -13063873857124, -113573062924024

Offset: 0

Author

Seiichi Manyama, Apr 23 2018

Keywords

• sign

Crossrefs

Expansion of Product_{n>=1} ((1 + (2^b*x)^n)/(1 - (2^b)*x^n))^(1/(2^b)): A002448 (b=0), A303306 (b=1), this sequence (b=2), A303395 (b=3).

Cf. A303361.

Programs

PARI

N=66; x='x+O('x^N); Vec(prod(k=1, N, ((1-(4*x)^k)/(1+(4*x)^k))^(1/4)))