%I #20 Jan 29 2021 18:58:02
%S 0,1,4,3,256,65,192,7,16777216,524289,2098176,8195,50331648,49153,
%T 114688,15,18446744073709551616,4503599627370497,36028797019226112,
%U 1099511627779,2305844108725321728,17592190238721,70368756760576,67108871,14167099448608935641088
%N a(n) is derived from n by replacing each 0 in its binary representation with a string of n 0's.
%H Alois P. Heinz, <a href="/A340667/b340667.txt">Table of n, a(n) for n = 0..500</a>
%F a(n) = n <=> n in { A000225 }.
%F a(n) = n^n <=> n in { A000079 }.
%F A000120(a(n)) = A000120(n).
%F A023416(a(n)) = n * A023416(n) for n >= 1.
%p a:= n-> Bits[Join](subs(0=[0$n][], Bits[Split](n))):
%p seq(a(n), n=0..25);
%p # second Maple program:
%p b:= proc(n, k) option remember; `if`(n<2, n,
%p `if`(irem(n, 2, 'r')=1, b(r, k)*2+1, b(r, k)*2^k))
%p end:
%p a:= n-> b(n$2):
%p seq(a(n), n=0..25);
%o (Python)
%o def A340667(n):
%o return 0 if n == 0 else int(bin(n)[2:].replace('0','0'*n),2) # _Chai Wah Wu_, Jan 29 2021
%Y Main diagonal of A340666.
%Y Cf. A000079, A000120, A000225, A023416, A057156.
%K nonn,look,base
%O 0,3
%A _Alois P. Heinz_, Jan 15 2021