|
Search: id:A098334
|
|
|
| A098334 |
|
Expansion of 1/sqrt(1-2x+17x^2). |
|
+0
3
|
|
| 1, 1, -7, -23, 49, 401, 41, -5767, -11423, 65569, 299353, -441847, -5511791, -3665999, 79937417, 212712857, -861871423, -5076450239, 3966949049, 89482678313, 110424995569, -1233175514671, -4202194115863
(list; graph; listen)
|
|
|
OFFSET
|
0,3
|
|
|
COMMENT
|
Central coefficients of (1+x-4x^2)^n. Binomial transform of 1/sqrt(1+16x^2), or (1,0,-8,0,96,0,-1280,...) Binomial transform is A098337.
|
|
REFERENCES
|
Tony D. Noe, On the Divisibility of Generalized Central Trinomial Coefficients, Journal of Integer Sequences, Vol. 9 (2006), Article 06.2.7.
|
|
FORMULA
|
E.g.f. : exp(x)BesselI(0, 4*I*x), I=sqrt(-1); a(n)=sum{k=0..floor(n/2), binomial(n, 2k)binomial(2k, k)(-4)^k}; a(n)=sum{k=0..floor(n/2), binomial(n, k)binomial(n-k, k)(-4)^k); a(n)=sum{k=0..n, binomial(n, k)binomial(k, k/2)cos(pi*k/2)2^k}3
|
|
CROSSREFS
|
Adjacent sequences: A098331 A098332 A098333 this_sequence A098335 A098336 A098337
Sequence in context: A162290 A062725 A147121 this_sequence A038796 A004068 A022815
|
|
KEYWORD
|
easy,sign
|
|
AUTHOR
|
Paul Barry (pbarry(AT)wit.ie), Sep 03 2004
|
|
|
Search completed in 0.002 seconds
|
