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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A237416 Smallest multiple of 5 beginning with n. 1
10, 20, 30, 40, 5, 60, 70, 80, 90, 10, 110, 120, 130, 140, 15, 160, 170, 180, 190, 20, 210, 220, 230, 240, 25, 260, 270, 280, 290, 30, 310, 320, 330, 340, 35, 360, 370, 380, 390, 40, 410, 420, 430, 440, 45, 460, 470, 480, 490, 50, 510, 520, 530, 540, 55, 560 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,2,0,0,0,0,-1).

FORMULA

G.f.: 5*x*(2 +4*x +6*x^2 +8*x^3 +x^4 +8*x^5 +6*x^6 +4*x^7 +2*x^8)/(1 -x^5)^2.

a(n) = 2*a(n-5) - a(n-10).

MATHEMATICA

Table[If[Mod[n, 5]==0, n, If[Mod[10 n, 5]==0, 10 n, 10 n + 5 - Mod[10 n, 5]]], {n, 60}] (* or *) CoefficientList[Series[5 (2 + 4 x + 6 x^2 + 8 x^3 + x^4 + 8 x^5 + 6 x^6 + 4 x^7 + 2 x^8)/(1 - x^5)^2, {x, 0, 40}], x]

PROG

I:=[10, 20, 30, 40, 5, 60, 70, 80, 90, 10]; [n le 10 select I[n] else 2*Self(n-5)-Self(n-10): n in [1..60]];

CROSSREFS

Cf. A082799 - A082804.

Sequence in context: A172260 A300024 A069534 * A236507 A031140 A095973

Adjacent sequences:  A237413 A237414 A237415 * A237417 A237418 A237419

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Feb 10 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 June 16 21:20 EDT 2019. Contains 324155 sequences. (Running on oeis4.)