|
Search: id:A145074
|
|
|
| A145074 |
|
a(n) = [x^(4^n)] Q(x,n)^(n+1) where Q(x,n) = Sum_{k=0..n} (x^(4^k) + x^(2*4^k) + x^(3*4^k)) for n>=0. |
|
+0
4
|
| |
|
|
OFFSET
|
0,2
|
|
|
EXAMPLE
|
a(n) equals the coefficient of x^(4^n) in Q(x,n)^(n+1) where
Q(x,n) = Sum_{k=0..n} (x^(4^k) + x^(2*4^k) + x^(3*4^k)) for n>=0.
|
|
PROGRAM
|
(PARI) {a(n, q=4)=local(Q=sum(j=0, n, (x^(q^j)-x^(q*q^j))/(1-x^(q^j)+O(x^(q^n+1))))); polcoeff(Q^(n+1), q^n)}
|
|
CROSSREFS
|
Cf. A007178, A145073, A145075, A145076.
Sequence in context: A025503 A078124 A115245 this_sequence A162055 A067300 A133359
Adjacent sequences: A145071 A145072 A145073 this_sequence A145075 A145076 A145077
|
|
KEYWORD
|
more,nonn
|
|
AUTHOR
|
Paul D. Hanna (pauldhanna(AT)juno.com), Oct 09 2008
|
|
|
Search completed in 0.004 seconds
|
