A043356 Numbers having four 1's in base 5.

156, 656, 756, 776, 780, 782, 783, 784, 786, 791, 796, 806, 831, 856, 906, 1031, 1156, 1406, 2031, 2656, 3156, 3256, 3276, 3280, 3282, 3283, 3284, 3286, 3291, 3296, 3306, 3331, 3356, 3406, 3531, 3656, 3756, 3776, 3780

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

F:= proc(d, m) option remember;
  local A, B;
  if m > d then return [] fi;
  if d = 0 then return [0] fi;
  A:= seq(seq(seq(t+i*5^(d-1), t=procname(dd, m)), dd = 0..d-1), i=2..4);
  if m = 0 then [A]
  else [seq(seq(t+5^(d-1), t=procname(dd, m-1)), dd=0..d-1), A]
  fi
end proc:
map(op, [seq(F(d, 4), d=4..6)]); # Robert Israel, Jul 02 2018

Prog

(PARI) isok(n) = #select(x->(x==1), digits(n, 5)) == 4; \\ Michel Marcus, Jul 02 2018

Crossrefs

Cf. A007091 (numbers in base 5).

Sequence in context: A250382 A106056 A259947 * A038476 A158550 A156994

Adjacent sequences: A043353 A043354 A043355 * A043357 A043358 A043359

Keyword

nonn,base

Author

Clark Kimberling

Status

approved