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A333415
Odd positive integers in base 2 read backwards.
1
1, 11, 101, 111, 1001, 1101, 1011, 1111, 10001, 11001, 10101, 11101, 10011, 11011, 10111, 11111, 100001, 110001, 101001, 111001, 100101, 110101, 101101, 111101, 100011, 110011, 101011, 111011, 100111, 110111, 101111, 111111, 1000001, 1100001, 1010001, 1110001, 1001001
OFFSET
1,2
LINKS
FORMULA
From Michel Marcus, Apr 23 2020: (Start)
a(n) = A007088(A145341(n)).
a(n) = A004086(A099821(n)). (End)
MAPLE
f:= proc(n) local L, i;
L:= convert(n, base, 2);
add(L[-i]*10^(i-1), i=1..nops(L));
end proc
map(f, [seq(i, i=1..100, 2)]); # Robert Israel, May 19 2024
MATHEMATICA
Table[FromDigits[Reverse[IntegerDigits[n, 2]]], {n, 1, 75, 2}] (* Amiram Eldar, Apr 27 2020 *)
PROG
(PARI) a(n) = fromdigits(Vecrev(binary(2*n-1))); \\ Michel Marcus, May 19 2024
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Devansh Singh, Mar 20 2020
EXTENSIONS
New name, a(1)=1 and more terms from Michel Marcus, Apr 23 2020
STATUS
approved