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A307746 Triangle read by rows, obtained by omitting all the 1's from the triangle in A307641 (except for the first row).

%I A307746 #65 Jul 01 2019 16:49:05
%S A307746 1,2,3,2,2,5,2,3,7,2,2,2,3,3,2,5,11,2,3,2,13,2,7,3,5,2,2,2,2,17,2,3,3,
%T A307746 19,2,2,5,3,7,2,11,23,2,3,2,2,5,5,2,13,3,3,3,2,2,7,29,2,3,5,31,2,2,2,
%U A307746 2,2,3,11,2,17,5,7,2,3,2,3,37,2,19,3,13
%N A307746 Triangle read by rows, obtained by omitting all the 1's from the triangle in A307641 (except for the first row).
%C A307746 Has same shape as the triangle in A027746. The first difference occurs at row 12.
%H A307746 Michel Marcus, <a href="/A307746/b307746.txt">Rows n=1..3000 of triangle, flattened</a> (first 131 rows from I. V. Serov)
%F A307746 Row(i) = {d|i, A014963(d) > 1} A014963(d).
%F A307746 For i > 1, T(i, A001222(i)) = A088387(i). This is the last term of the i-th row.
%e A307746 Triangle begins:
%e A307746 1;
%e A307746 2;
%e A307746 3;
%e A307746 2, 2;
%e A307746 5;
%e A307746 2, 3;
%e A307746 7;
%e A307746 2, 2, 2;
%e A307746 3, 3;
%e A307746 2, 5;
%e A307746 11;
%e A307746 2, 3, 2;
%e A307746 ...
%o A307746 (PARI) f(n)=ispower(n, , &n); if(isprime(n), n, 1); \\ A014963
%o A307746 row(n) = if (n==1, [1], my(d=divisors(n)); select(x->x!=1, vector(#d, k, f(d[k]))));
%o A307746 tabl(nn) = for (n=1, nn, print(row(n))); \\ _Michel Marcus_, Apr 27 2019
%Y A307746 Cf. A088387, A014963, A027746, A307641.
%K A307746 nonn,tabf
%O A307746 1,2
%A A307746 _I. V. Serov_, Apr 26 2019