login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A245923 G.f.: (1-x + sqrt(1 - 14*x + x^2)) / (2*(1 - 14*x + x^2)). 3
1, 10, 127, 1684, 22717, 309214, 4231675, 58117672, 800173945, 11037041074, 152448280183, 2107959984316, 29172777600565, 404016491894662, 5598523988234227, 77617624970307664, 1076533162210721521, 14936507761662251866, 207302489038473478255, 2877906561872502533860 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Self-convolution of A245926.

Limit a(n+1)/a(n) = 7 + 4*sqrt(3).

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..870

FORMULA

a(n) ~ (7+4*sqrt(3))^(n+1) * (2-sqrt(3))/8 * (1+1/(3^(1/4)*sqrt(Pi*n/2))). - Vaclav Kotesovec, Aug 17 2014

EXAMPLE

G.f.: A(x) = 1 + 10*x + 127*x^2 + 1684*x^3 + 22717*x^4 + 309214*x^5 +...

MATHEMATICA

CoefficientList[Series[(1 - x + Sqrt[1 - 14*x + x^2])/(2*(1 - 14*x + x^2)), {x, 0, 50}], x] (* G. C. Greubel, Feb 14 2017 *)

PROG

(PARI) {a(n)=polcoeff( (1-x + sqrt(1-14*x+x^2 +x*O(x^n))) / (2*(1-14*x+x^2 +x*O(x^n))), n)}

for(n=0, 20, print1(a(n), ", "))

CROSSREFS

Cf. A245924, A245926.

Sequence in context: A192600 A079241 A270965 * A218474 A234284 A296379

Adjacent sequences:  A245920 A245921 A245922 * A245924 A245925 A245926

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Aug 16 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 21 23:29 EST 2019. Contains 320381 sequences. (Running on oeis4.)