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!)
A045800 0-ish numbers (end in 01, 07, 43, 49). 10
1, 7, 43, 49, 101, 107, 143, 149, 201, 207, 243, 249, 301, 307, 343, 349, 401, 407, 443, 449, 501, 507, 543, 549, 601, 607, 643, 649, 701, 707, 743, 749, 801, 807, 843, 849, 901, 907, 943, 949, 1001, 1007, 1043, 1049, 1101, 1107, 1143, 1149, 1201, 1207 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

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

FORMULA

G.f.: x*(1+6*x+36*x^2+6*x^3+51*x^4)/(1-x-x^4+x^5). - Colin Barker, Jan 23 2012

a(n) = (50*n-8*i^(n*(n+1))-19*(-1)^n-75)/2, where i=sqrt(-1). - Bruno Berselli, Feb 22 2012

MATHEMATICA

LinearRecurrence[{1, 0, 0, 1, -1}, {1, 7, 43, 49, 101}, 60] (* Harvey P. Dale, Jul 26 2015 *)

PROG

(Haskell)

import Data.List (findIndices)

a045800 n = a045800_list !! (n-1)

a045800_list = findIndices (`elem` [1, 7, 43, 49]) $ cycle [0..99]

-- Reinhard Zumkeller, Jan 23 2012

CROSSREFS

Cf. A045801-A045809, A045572, A045797, A045798.

Sequence in context: A043064 A175159 A173828 * A159254 A062336 A085704

Adjacent sequences:  A045797 A045798 A045799 * A045801 A045802 A045803

KEYWORD

nonn,base,easy

AUTHOR

J. H. Conway.

EXTENSIONS

More terms from Erich Friedman.

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 19 19:21 EST 2020. Contains 332047 sequences. (Running on oeis4.)