|
Search: id:A131964
|
|
|
| A131964 |
|
Expansion of phi(-q^4)* chi(-q^6)/ chi(-q) in powers of q where phi(), chi() are Ramanujan theta functions. |
|
+0
5
|
|
| 1, 1, 1, 2, 0, 1, 1, 0, 1, 0, 2, 1, 1, 1, 0, 1, 2, 2, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 2, 1, 1, 0, 1, 1, 1, 3, 0, 0, 0, 2, 1, 1, 2, 1, 2, 1, 0, 0, 0, 2, 1, 0, 2, 0, 2, 0, 0, 1, 1, 0, 1, 0, 1, 2, 1, 2, 1, 1, 1, 1, 0, 0, 0, 2, 1, 2, 0, 2, 2, 1, 1, 0, 0, 1, 3, 1, 0, 1, 1, 0, 1, 2, 1, 0, 1, 1, 0, 0, 2, 1, 0, 0
(list; graph; listen)
|
|
|
OFFSET
|
0,4
|
|
|
FORMULA
|
Expansion of q^(-19/24)* eta(q^2)* eta(q^4)^2* eta(q^6)* eta(q^24)/( eta(q)* eta(q^8)* eta(q^12)) in powers of q.
Euler transform of period 24 sequence [ 1, 0, 1, -2, 1, -1, 1, -1, 1, 0, 1, -2, 1, 0, 1, -1, 1, -1, 1, -2, 1, 0, 1, -2, ...].
a(25n+19)= a(n). a(25n+4)= a(25n+9)= a(25n+14)= a(25n+24)= 0.
|
|
PROGRAM
|
(PARI) {a(n)= if(n<0, 0, n=24*n+19; sumdiv(n, d, kronecker( -12, d)*(n/d %2))/2)}
(PARI) {a(n)= local(A); if(n<0, 0, A= x*O(x^n); polcoeff( eta(x^2+A)* eta(x^4+A)^2* eta(x^6+A)* eta(x^24+A)/ eta(x+A)/ eta(x^8+A)/ eta(x^12+A), n))}
|
|
CROSSREFS
|
Cf. A123484(24n+19)= 2*a(n).
Sequence in context: A025427 A091586 A116377 this_sequence A065339 A122434 A141571
Adjacent sequences: A131961 A131962 A131963 this_sequence A131965 A131966 A131967
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Michael Somos, Aug 02 2007
|
|
|
Search completed in 0.002 seconds
|
