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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A052462 a(n) is the solution k to Mod[24k,5^n]==1. 5
4, 24, 99, 599, 2474, 14974, 61849, 374349, 1546224, 9358724, 38655599, 233968099, 966389974, 5849202474, 24159749349, 146230061849, 603993733724, 3655751546224, 15099843343099, 91393788655599, 377496083577474 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Related to a Ramanujan congruence for the partition function P.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Eric Weisstein's World of Mathematics, Partition Function P Congruences.

Index entries for linear recurrences with constant coefficients, signature (1,25,-25).

FORMULA

G.f.: x(-25x^2+20x+4)/[(1-x)(1-5x)(1+5x)].

a(n) = (1+(21+2*(-1)^n)*5^n)/24  - Bruno Berselli, Apr 04 2011

a(n) = a(n-1) +25*a(n-2) -25*a(n-3). - Vincenzo Librandi, Jul 01 2012

MATHEMATICA

Table[PowerMod[24, -1, 5^a], {a, 21}]

CoefficientList[Series[(-25x^2+20x+4)/((1-x)(1-5x)(1+5x)), {x, 0, 30}], x] (* Vincenzo Librandi, Jul 01 2012 *)

PROG

(MAGMA) I:=[4, 24, 99]; [n le 3 select I[n] else Self(n-1)+25*Self(n-2)-25*Self(n-3): n in [1..30]]; // Vincenzo Librandi, Jul 01 2012

CROSSREFS

Cf. A052463, A052465, A052466.

Sequence in context: A100738 A139238 A139231 * A260217 A048806 A043009

Adjacent sequences:  A052459 A052460 A052461 * A052463 A052464 A052465

KEYWORD

nonn,easy

AUTHOR

Eric W. Weisstein

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 December 8 14:38 EST 2019. Contains 329865 sequences. (Running on oeis4.)