cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A286660 a(n) = a(n-1) + sum of base-100 digits of a(n-1), a(0) = 1.

Original entry on oeis.org

1, 2, 4, 8, 16, 32, 64, 128, 157, 215, 232, 266, 334, 371, 445, 494, 592, 689, 784, 875, 958, 1025, 1060, 1130, 1171, 1253, 1318, 1349, 1411, 1436, 1486, 1586, 1687, 1790, 1897, 2012, 2044, 2108, 2137, 2195, 2311, 2345, 2413, 2450, 2524, 2573, 2671, 2768, 2863, 2954, 3037, 3104, 3139
Offset: 0

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Author

Peter Weiss, May 12 2017

Keywords

Examples

			a(7) = 128 = 1 * 100^1 + 28 * 100^0. The sum of digits of a(8 - 1) = 128 in base 100 is therefore 1 + 28 = 29. a(8) = a(7) + the sum of digits of a(7) in base 100 is therefore 128 + 29 = 157.
		

Crossrefs

Programs

  • Maple
    g:= n -> n+convert(convert(n,base,100),`+`):
    A[0]:= 1:
    for n from 1 to 100 do A[n]:= g(A[n-1]) od:
    seq(A[i],i=0..100); # Robert Israel, May 22 2017
  • Mathematica
    a[0] = 1; a[n_] := a[n] = a[n-1] + Total[IntegerDigits[a[n-1], 100]];
    Table[a[n], {n, 0, 100}] (* Jean-François Alcover, May 21 2017 *)
    NestList[#+Total[IntegerDigits[#,100]]&,1,60] (* Harvey P. Dale, May 26 2019 *)
  • PARI
    a(n) = if(n < 8, return(1<<(n-1))); my(r = cr = 128); for(i=8, n, while(cr > 0, r += cr % 100; cr \= 100); cr = r); r \\ David A. Corneth, May 15 2017