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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A094623 Expansion of x*(1+10*x)/((1-x)*(1-10*x^2)). 3
 0, 1, 11, 21, 121, 221, 1221, 2221, 12221, 22221, 122221, 222221, 1222221, 2222221, 12222221, 22222221, 122222221, 222222221, 1222222221, 2222222221, 12222222221, 22222222221, 122222222221, 222222222221, 1222222222221 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Previous name was: Sequence whose n-th term digits sum to n. n-th term digits are reversals of A094624(n). LINKS Index entries for linear recurrences with constant coefficients, signature (1,10,-10). FORMULA G.f.: x*(1+10*x)/((1-x)*(1-10*x^2)). a(n) = (10^(n/2)/2)*(11/9 + 2*sqrt(10)/9 - (2*sqrt(10)/9 - 11/9)*(-1)^n) - 11/9. CROSSREFS Cf. A094624, A094625, A094626. Sequence in context: A126299 A166707 A116525 * A321509 A034922 A015446 Adjacent sequences:  A094620 A094621 A094622 * A094624 A094625 A094626 KEYWORD easy,nonn,base AUTHOR Paul Barry, May 15 2004 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.

Last modified June 18 20:45 EDT 2021. Contains 345121 sequences. (Running on oeis4.)