OFFSET
0,3
LINKS
FORMULA
a(n) = 10*A007088(floor(n/3)) + (n mod 3).
G.f.: x*(1+2*x)/(1-x^3) + 10/(1-x) * Sum_{k>=0} 10^k*x^(3*2^k)/(1 + x^(3*2^k)).
PROG
(PARI) a(n) = my(r); [n, r]=divrem(n, 3); fromdigits(concat(binary(n), r));
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Kevin Ryde, Apr 24 2021
STATUS
approved