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.

A194854 Starting from a(1)=1, describe previous terms and then add all the digits.

Original entry on oeis.org

1, 2, 5, 11, 13, 18, 28, 30, 32, 34, 40, 42, 44, 46, 54, 56, 58, 60, 62, 64, 66, 68, 70, 79, 90, 92, 94, 96, 98, 100, 103, 106, 100, 94, 87, 89, 91, 84, 86, 88, 81, 83, 85, 87, 89, 82, 84, 86, 88, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 104, 107, 110, 113
Offset: 1

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Author

Paolo P. Lava, Sep 07 2011

Keywords

Examples

			Start with 1. There is one 1: 11 and 1+1=2. The sequence is now 1,2. Therefore one 1 and one 2: 1112 and 1+1+1+2=5. The sequence is now 1,2,5. Again: 111215 and 1+1+1+2+1+5=11. And so on.
		

Crossrefs

Programs

  • Maple
    sd:=proc(j)
    local c,d,h,k;
    h:=j; c:=0;
    if h>0 then
       d:=floor(evalf(log10(h))+1);
       for k from 1 to d do c:=c+h-10*trunc(h/10); h:=trunc(h/10); od;
    fi;
    c;
    end:
    P:=proc(i)
    local a,b,f,n,p,s,v;
    v:=array[10]; v[1]:=1; v[10]:=0; print(v[1]);
    for n from 2 to 9 do v[n]:=0; od;
    for n from 1 by 1 to i do
       a:=0;
       for p from 1 to 10 do
         if sd(v[p])=0 then a:=a+sd(v[p]);
         else a:=a+(p mod 10)+sd(v[p]);
         fi;
       od;
       print(a); s:=floor(evalf(log10(a))+1);
       for p from 1 to s do
         f:=a-10*trunc(a/10); a:=trunc(a/10);
         if f=0 then v[10]:=v[10]+1; else v[f]:=v[f]+1; fi;
       od;
    od;
    end:
    P(10000);