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A378308 Array read by antidiagonals: For k >= 3, row k-2 consists of the numbers with no digits 0 in bases 3 to k.

Original entry on oeis.org

1, 2, 1, 4, 2, 1, 5, 5, 2, 1, 7, 7, 7, 2, 1, 8, 13, 13, 7, 2, 1, 13, 14, 14, 13, 13, 2, 1, 14, 22, 22, 14, 22, 13, 2, 1, 16, 23, 23, 22, 23, 22, 13, 2, 1, 17, 25, 41, 23, 43, 23, 22, 13, 2, 1, 22, 26, 43, 43, 121, 43, 23, 22, 13, 2, 1, 23, 41, 121, 121, 122, 121, 43, 23, 23, 13, 2, 1, 25, 43, 122
Offset: 1

Views

Author

Robert Israel, Nov 22 2024

Keywords

Comments

Row k-2 consists of 1, 2 and numbers x with A270027(x) > k.

Examples

			Array starts
  1,   2,   4,   5,    7,    8,   13,   14,   16,   17,   22,   23, ...
  1,   2,   5,   7,   13,   14,   22,   23,   25,   26,   41,   43, ...
  1,   2,   7,  13,   14,   22,   23,   41,   43,  121,  122,  157, ...
  1,   2,   7,  13,   14,   22,   23,   43,  121,  122,  157,  158, ...
  1,   2,  13,  22,   23,   43,  121,  122,  157,  158,  214,  607, ...
  1,   2,  13,  22,   23,   43,  121,  122,  157,  158,  214,  607, ...
  1,   2,  13,  22,   23,   43,  121,  122,  157,  158,  214,  607, ...
  1,   2,  13,  22,   23,   43,  121,  122,  157,  158,  214,  619, ...
  1,   2,  13,  23,   43,  157,  158,  214,  619, 5471, 5557, 5561, ...
  1,   2,  13,  23,   43,  157,  158,  214,  619, 5471, 5557, 5561, ...
  1,   2,  23,  43,  157,  158,  214,  619, 5471, 5557, 5561, 5791, ...
  1,   2,  23,  43,  157,  158,  214,  619, 5471, 5791, 5821, 5822, ...
  1,   2,  23,  43,  157,  158,  214,  619, 5471, 5791, 5821, 5822, ...
		

Crossrefs

Cf. A270027.

Programs

  • Maple
    g:= proc(x,d) local L,i;
      L:= convert(2^d+x,base,2);
      add((L[i]+1)*3^(i-1),i=1..d)
    end proc:
    T3:= NULL:
    for d from 1 to 14 do T3:= T3, seq(g(x,d),x=0..2^d-1); od:
    T[3]:= [T3]:
    for b from 4 to 14 do T[b]:= remove(t -> member(0, convert(t,base,b)),T[b-1]); if nops(T[b]) = 0 then printf("b=%d\n",b); break fi; od:
    for b from 3 to 14 do T[b][1..14] od;