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!)
A206244 Number of partitions of n into repunits (A002275). 3
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,12

COMMENTS

a(n) = A206245(n) for n <= 120, a(n) < A206245(n) for n > 120.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..1000

Eric Weisstein's World of Mathematics, Repunit

Wikipedia, Repunit

Index entries for related partition-counting sequences

FORMULA

G.f.: Product_{k>=1} 1/(1 - x^((10^k-1)/9)). - Ilya Gutkovskiy, Jul 26 2017

EXAMPLE

a(12)=2 is the first nontrivial term, from the partitions 12 = 1+1+...+1 = 11+1. - N. J. A. Sloane, Jul 26 2017

MATHEMATICA

With[{nn = 50}, Table[Count[IntegerPartitions@ n, k_ /; ContainsAll[Array[Floor[10^#/9] &, IntegerLength[nn + 1]], Union@ k]], {n, 0, nn}]] (* Michael De Vlieger, Jul 26 2017 *)

PROG

(Haskell)

a206244 = p $ tail a002275_list where

   p _             0 = 1

   p rus'@(ru:rus) n = if n < ru then 0 else p rus' (n - ru) + p rus n

CROSSREFS

Cf. A000041, A002275, A179051.

Sequence in context: A287272 A300287 A226764 * A206245 A064458 A125891

Adjacent sequences:  A206241 A206242 A206243 * A206245 A206246 A206247

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Feb 05 2012

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 April 21 19:16 EDT 2021. Contains 343156 sequences. (Running on oeis4.)