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A095167 Triangle read by rows in which the n-th row contains n numbers noncoprime to n and not occurring in earlier rows.

%I A095167 #9 Jun 05 2015 05:18:17
%S A095167 1,2,4,3,6,9,8,10,12,14,5,15,20,25,30,16,18,21,22,24,26,7,28,35,42,49,
%T A095167 56,63,32,34,36,38,40,44,46,48,27,33,39,45,51,54,57,60,66,50,52,55,58,
%U A095167 62,64,65,68,70,72,11,77,88,99,110,121,132,143,154,165,176,69,74,75,76
%N A095167 Triangle read by rows in which the n-th row contains n numbers noncoprime to n and not occurring in earlier rows.
%C A095167 Rearrangement of natural numbers so that next n numbers are not coprime to n.
%H A095167 Ivan Neretin, <a href="/A095167/b095167.txt">Rows n = 1..141, flattened</a>
%e A095167 1
%e A095167 2 4
%e A095167 3 6 9
%e A095167 8 10 12 14
%e A095167 5 15 20 25 30
%e A095167 16 18 21 22 24 26
%e A095167 7 28 35 42 49 56 63
%e A095167 ...
%t A095167 Fold[Function[{a, n}, Join[a, Select[Complement[Range[Max[a] + n^2], a], GCD[n, #] > 1 &, n]]], {1}, Range[2, 12]] (* _Ivan Neretin_, Jun 05 2015 *)
%o A095167 (PARI) S=Set();for(n=2,20,k=0;m=1;while(k<n,m++;if(!setsearch(S,m)&&gcd(m,n)>1,S=setunion(S,[m]);print1(" ",m);k++))) (Alekseyev)
%Y A095167 Cf. A095168, A095169, A095170, A095171.
%Y A095167 Cf. A081964 (coprime instead of non-coprime).
%K A095167 nonn,tabl
%O A095167 1,2
%A A095167 _Amarnath Murthy_, Jun 01 2004
%E A095167 More terms from _Max Alekseyev_, Jun 30 2005