cp's OEIS Frontend

A279160 Irregular triangle read by rows in which row n lists the perimeters of the parts of the symmetric representation of sigma(n).

%I A279160 #18 Dec 12 2016 09:00:59
%S A279160 4,8,6,6,16,8,8,24,10,10,32,12,8,12,20,20,14,14,48,16,16,26,26,18,16,
%T A279160 18,64
%N A279160 Irregular triangle read by rows in which row n lists the perimeters of the parts of the symmetric representation of sigma(n).
%e A279160 4;
%e A279160 8;
%e A279160 6, 6;
%e A279160 16;
%e A279160 8, 8;
%e A279160 24;
%e A279160 10, 10;
%e A279160 32;
%e A279160 12, 8, 12;
%e A279160 20, 20;
%e A279160 14, 14;
%e A279160 48;
%e A279160 16, 16;
%e A279160 26, 26;
%e A279160 18, 16, 18;
%e A279160 64;
%e A279160 ...
%e A279160 Illustration of the 9th row:
%e A279160 .         12
%e A279160 .     _ _ _ _ _
%e A279160 .    |_ _ _ _ _|
%e A279160 .               _ _ 8
%e A279160 .              |_  |
%e A279160 .                |_|  _
%e A279160 .                    | |
%e A279160 .                    | |
%e A279160 .                    | |  12
%e A279160 .                    | |
%e A279160 .                    |_|
%e A279160 .
%e A279160 For n = 9 the symmetric representation of sigma(9) = 13 has three parts of areas 5, 3, 5 respectively. The perímeters of the parts are 12, 8 and 12 as shown above, so the 9th row of triangle is 12, 8, 12.
%Y A279160 Twice A278447.
%Y A279160 Row sums give A274919.
%Y A279160 Cf. A237271 gives the row lengths.
%Y A279160 Cf. A000203, A196020, A235791, A236104, A237270, A237591, A237593, A245092, A262626.
%K A279160 nonn,tabf,more
%O A279160 1,1
%A A279160 _Omar E. Pol_, Dec 07 2016