login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A049395 Expansion of (1-25*x)^(-7/5). 2
1, 35, 1050, 29750, 818125, 22089375, 589050000, 15567750000, 408653437500, 10670395312500, 277430278125000, 7187966296875000, 185689129335937500, 4785066025195312500, 123044554933593750000, 3158143576628906250000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Robert Israel, Table of n, a(n) for n = 0..713

FORMULA

G.f.: (1-25*x)^(-7/5).

a(n) = (5^n/n!) * Product_{k=0..n-1} (5*k+7).

a(n) ~ 5/2*Gamma(2/5)^-1*n^(2/5)*5^(2*n)*{1 + 7/25*n^-1 - ...}. - Joe Keane (jgk(AT)jgk.org), Nov 24 2001

a(n) = (25+10/n)*a(n-1) for n >= 1. - Robert Israel, Mar 15 2020

MAPLE

f:= gfun:-rectoproc({a(n) = (25+10/n)*a(n-1), a(0) = 1}, a(n), remember):

map(f, [$1..50]); # Robert Israel, Mar 15 2020

MATHEMATICA

CoefficientList[Series[(1-25*x)^(-7/5), {x, 0, 15}], x] (* Georg Fischer, Jan 16 2020 *)

PROG

(MAGMA) R<x>:=PowerSeriesRing(Rationals(), 16); Coefficients(R!( (1-25*x)^(-7/5) )); // Marius A. Burtea, Jan 16 2020

CROSSREFS

Cf. A049380.

Sequence in context: A002453 A240826 A210313 * A278723 A215296 A209180

Adjacent sequences:  A049392 A049393 A049394 * A049396 A049397 A049398

KEYWORD

nonn,easy

AUTHOR

Joe Keane (jgk(AT)jgk.org)

EXTENSIONS

Typo in name corrected by Georg Fischer, Jan 16 2020

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 November 27 07:28 EST 2021. Contains 349365 sequences. (Running on oeis4.)