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!)
A001369 Blocks of increasing length using 1,2,3,...,9,10; omit leading 0's. 3
1, 23, 456, 7891, 1234, 567891, 123456, 78910123, 456789101, 2345678910, 12345678910, 123456789101, 2345678910123, 45678910123456, 789101234567891, 123456789101234, 56789101234567891, 12345678910123456, 7891012345678910123, 45678910123456789101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

It appears that the first digit repeats 1, 2, 4, 7, 1, 5, 1, 7, 4, 2, 1. - T. D. Noe, Apr 05 2011

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..200

MATHEMATICA

nn = 20; d = Flatten[Table[{1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 0}, {Ceiling[nn (nn + 1)/22]}]]; Table[e = (n + 1) n/2; s = e - n + 1; FromDigits[d[[s ;; e]]], {n, nn}] (* T. D. Noe, Apr 05 2011 *)

PROG

(PARI) N=[]; k=Mod(-1, 10); for(n=1, 20, while(#N<n, N=concat(N, Vec(Str(1+lift(k++))))); print1(eval(concat(vecextract(N, 2^n-1)))", "); N=vecextract(N, Str("^.."n))) \\ M. F. Hasler, May 08 2014

CROSSREFS

Cf. A066547, A007923.

Sequence in context: A076068 A062273 A066547 * A007923 A080479 A053067

Adjacent sequences:  A001366 A001367 A001368 * A001370 A001371 A001372

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane.

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 21:55 EDT 2021. Contains 345080 sequences. (Running on oeis4.)