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%I #31 Jan 11 2020 15:57:47
%S 1,8,19,27,74,185,440,1015,2294,5109,10228,11252,24563,53234,114673,
%T 245744,524271,1114094,2359277,4980716,10485739,22020074,46137321,
%U 88080360,96468968,201326567,419430374,872415205,1811939300,15569256417
%N Values of f(2,x,y) in increasing order, for x>=0, y>0 where f is the Sudan function defined in A260002.
%C This is a subsequence of A260003 since f(2,x,y)= f(1, f(2,x,y-1), f(2,x,y-1)+y).
%C In this list we suppose that y>0. If we take y=0, all the natural numbers would be in the sequence.
%C To evaluate the Sudan function see A260002-A260003.
%e f(2,0,1) = f(1, f(2,0,0), f(2,0,0)+1) = f(1,0,1) = 2^1(0+2)-1-2 = 1;
%e f(2,0,2) = f(1, [f(2,0,1)], [f(2,0,1)+1+1]) = f(1,1,3) = 2^3(1+2)-3-2 = 19;
%Y Cf. A048493 (f(2,n,1)), A260002, A260003, A260005 (f(2,n,2)), A260006.
%K nonn
%O 1,2
%A _Natan Arie Consigli_, Jul 23 2015