A032940 Numbers whose base-5 representation Sum_{i=0..m} d(i)*5^(m-i) has d(i)=0 for all odd i.

1, 2, 3, 4, 5, 10, 15, 20, 25, 26, 27, 28, 29, 50, 51, 52, 53, 54, 75, 76, 77, 78, 79, 100, 101, 102, 103, 104, 125, 130, 135, 140, 145, 250, 255, 260, 265, 270, 375, 380, 385, 390, 395, 500, 505, 510, 515, 520, 625, 626, 627, 628, 629

Offset: 1

Author

Clark Kimberling

Keywords

• nonn
• base

Links

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

Crossrefs

Cf. A007091 (numbers in base 5).

Programs

Maple

f:= proc(n,j) local L,m;
  L:= convert(n,base,5);
  m:= nops(L);
  j*add(L[i+1]*5^(2*i),i=0..m-1)
end proc:
seq(seq(seq(f(n,j),n=5^k..5^(k+1)-1),j=[1,5]),k=0..2); # Robert Israel, Nov 15 2020

Extensions

Definition corrected by Robert Israel, Nov 15 2020