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%I #7 Oct 11 2019 13:57:42
%S 1,4,3,12,10,18,35,32,9,40,55,48,26,84,105,112,17,54,76,100,231,198,
%T 23,120,25,156,162,280,203,150,31,192,264,68,245,288,222,418,468,440,
%U 82,294,301,352,405,368,141,432,98,600,714,520,424,702,275,672,513,928,177
%N Smallest positive number divisible by n which is not of the form a(i) or a(i)+a(j) for i and j <= n-1.
%C Same as A122537, except that a(n) is allowed to be less than a(n-1) (but not equal to it, or any other previous term).
%H Alois P. Heinz, <a href="/A122544/b122544.txt">Table of n, a(n) for n = 1..1000</a>
%p a:=array(0..100000); m:=array(0..100000); hit:=array(0..100000); B:=100000; M:=120;
%p for n from 1 to B do hit[n]:=0; od:
%p a[1]:=1; m[1]:=1; a[2]:=4; m[2]:=2; hit[2]:=1; hit[5]:=1; hit[8]:=1; hit[1]:=1; hit[4]:=1;
%p for n from 3 to M do i:=n; while hit[i] = 1 do i:=i+n; od; a[n]:= i; m[n]:= i/n; hit[i]:=1;
%p for j from 1 to n do hit[a[j]+i]:=1; od; od:
%p t1:=[seq(a[n],n=1..M)]; t2:=[seq(m[n],n=1..M)];
%t f[s_] := Block[{n, k},k = n = Length[s] + 1;While[MemberQ[Union[s, Plus @@@ Tuples[s, 2]], k], k += n];Append[s, k]];Nest[f, {1}, 60] (* _Ray Chandler_, Sep 29 2006 *)
%Y Cf. A122537, A122545 (a(n)/n), A122546 (complement), A122804.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Sep 20 2006
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