A032942 Numbers whose base-7 representation Sum_{i=0..m} d(i)*7^(m-i) has d(i)=0 for all odd i.

1, 2, 3, 4, 5, 6, 7, 14, 21, 28, 35, 42, 49, 50, 51, 52, 53, 54, 55, 98, 99, 100, 101, 102, 103, 104, 147, 148, 149, 150, 151, 152, 153, 196, 197, 198, 199, 200, 201, 202, 245, 246, 247, 248, 249, 250, 251, 294, 295, 296, 297, 298

Offset

1,2

Links

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

Maple

f:= proc(n, j) local L, m;
  L:= convert(n, base, 5);
  m:= nops(L);
  j*add(L[i+1]*7^(2*i), i=0..m-1)
end proc: seq(seq(seq(f(n, j), n=7^k..7^(k+1)-1), j=[1, 7]), k=0..2); # Robert Israel, Nov 16 2020

Crossrefs

Cf. A007093 (numbers in base 7).

Sequence in context: A032886 A023789 A032996 * A273734 A115308 A171649

Adjacent sequences: A032939 A032940 A032941 * A032943 A032944 A032945

Keyword

nonn,base

Author

Clark Kimberling

Extensions

Definition corrected by Robert Israel, Nov 16 2020

Status

approved