OFFSET
2,1
COMMENTS
a(n) is the leading power of 2 in M(n) = A230303(n).
LINKS
Max A. Alekseyev and N. J. A. Sloane, On Kaprekar's Junction Numbers, arXiv:2112.14365, 2021; Journal of Combinatorics and Number Theory 12:3 (2022), 115-155.
EXAMPLE
The terms after 8206 are 2^136+4110, 2^137+14, 2^260+2^136+136, 2^261+262, 2^4233+2^260+260, ... (see also A230303).
MAPLE
f:=proc(n) option remember; local B, M;
if n<=1 then RETURN([0, 0]);
else
if (n mod 2) = 0 then B:=2*f(n/2)[2]+2;
else B:=f((n+1)/2)[2]+f((n-1)/2)[2]+2; fi;
M:=2^B+f(floor(n/2))[2]+1; RETURN([B, M]); fi;
end proc;
[seq(f(n)[1], n=1..7)];
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Oct 24 2013
EXTENSIONS
a(11) corrected, expressions for a(2)-a(100) added by Max Alekseyev, Nov 02 2013
STATUS
approved