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A327856 The upper left triangular section of square array A091255, read by rows.

%I A327856 #7 Sep 28 2019 22:24:36
%S A327856 1,1,2,1,1,3,1,2,1,4,1,1,3,1,5,1,2,3,2,3,6,1,1,1,1,1,1,7,1,2,1,4,1,2,
%T A327856 1,8,1,1,3,1,3,3,7,1,9,1,2,3,2,5,6,1,2,3,10,1,1,1,1,1,1,1,1,1,1,11,1,
%U A327856 2,3,4,3,6,1,4,3,6,1,12,1,1,1,1,1,1,1,1,1,1,1,1,13,1,2,1,2,1,2,7,2,7,2,1,2,1,14
%N A327856 The upper left triangular section of square array A091255, read by rows.
%H A327856 Antti Karttunen, <a href="/A327856/b327856.txt">Table of n, a(n) for n = 1..10440; the first 144 rows of triangular table</a>
%H A327856 <a href="/index/Ge#GF2X">Index entries for sequences operating on polynomials in ring GF(2)[X]</a>
%F A327856 A(n,k) = A091255(n,k), with k in range 1 .. n.
%F A327856 a(A000217(n)) = n.
%e A327856 The triangular table starts as:
%e A327856   1,
%e A327856   1, 2,
%e A327856   1, 1, 3,
%e A327856   1, 2, 1, 4,
%e A327856   1, 1, 3, 1, 5,
%e A327856   1, 2, 3, 2, 3, 6,
%e A327856   1, 1, 1, 1, 1, 1, 7,
%e A327856   1, 2, 1, 4, 1, 2, 1, 8,
%e A327856   1, 1, 3, 1, 3, 3, 7, 1, 9,
%e A327856   1, 2, 3, 2, 5, 6, 1, 2, 3, 10,
%e A327856   ...
%o A327856 (PARI)
%o A327856 up_to = 105;
%o A327856 A091255sq(a,b) = fromdigits(Vec(lift(gcd(Pol(binary(a))*Mod(1, 2),Pol(binary(b))*Mod(1, 2)))),2);
%o A327856 A327856list(up_to) =  { my(v = vector(up_to), i=0); for(a=1,oo, for(col=1,a, i++; if(i > up_to, return(v)); v[i] = A091255sq(a,col))); (v); };
%o A327856 v327856 = A327856list(up_to);
%o A327856 A327856(n) = v327856[n];
%Y A327856 Cf. A000217, A091255.
%K A327856 nonn,tabl
%O A327856 1,3
%A A327856 _Antti Karttunen_, Sep 28 2019