OFFSET
1,1
COMMENTS
The range of the sequence is generated by the context-sensitive grammar with decimal digits as terminals, {s,x,y,z,c,u,v,L,R} as non-terminals, s as axiom and the following rules (e is the empty word): s->L1xy1R, L->e, R->e, xy->e, 0x->1u, 1x->x0, Lx->L1u, u1->1u, u0->0u, uy->uz, zi->iz for 0<=i<=9, ziR->vjR for j=i+1 and 0<=i<9, z9R->c0R, ic->vj for j=i+1 and 0<=i<9, 9c->c0, iv->vi for 0<=i<=9, uv->xy and uc->xy1.
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..10000
MAPLE
a:= n-> parse(cat(convert(n, binary), n)):
seq(a(n), n=1..35); # Alois P. Heinz, Jul 31 2022
MATHEMATICA
Table[FromDigits[Join[IntegerDigits[n, 2], IntegerDigits[n]]], {n, 30}] (* Harvey P. Dale, Dec 13 2011 *)
PROG
(Python)
def a(n): return int(bin(n)[2:]+str(n))
print([a(n) for n in range(1, 34)]) # Michael S. Branicky, Jul 31 2022
(PARI) a(n) = fromdigits(binary(n))*10^(logint(n, 10)+1) + n; \\ Kevin Ryde, Nov 10 2022
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Reinhard Zumkeller, Oct 02 2003
EXTENSIONS
a(30) and beyond from Michael S. Branicky, Jul 31 2022
STATUS
approved