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A302248 Irregular triangle read by rows in which the odd-indexed terms of the n-th row together with the even-indexed terms of the same row but listed in reverse order give the n-th row of triangle A299778.

%I A302248 #23 May 19 2022 16:43:55
%S A302248 1,3,2,2,7,0,3,3,12,0,0,4,4,0,15,0,0,5,5,3,9,0,0,9,6,6,0,0,28,0,0,0,7,
%T A302248 7,0,0,12,0,0,12,8,8,8,0,0,31,0,0,0,0,9,9,0,0,0,39,0,0,0,0,10,10,0,0,
%U A302248 0,42,0,0,0,0,11,11,5,0,0,5,18,0,0,18,0,0,12,12,0,0,0,0,60,0,0,0,0,0,13,13,0,0,5,0
%N A302248 Irregular triangle read by rows in which the odd-indexed terms of the n-th row together with the even-indexed terms of the same row but listed in reverse order give the n-th row of triangle A299778.
%H A302248 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%e A302248 Triangle begins (rows 1..28):
%e A302248    1;
%e A302248    3;
%e A302248    2,  2;
%e A302248    7,  0;
%e A302248    3,  3;
%e A302248   12,  0,  0;
%e A302248    4,  4,  0;
%e A302248   15,  0,  0;
%e A302248    5,  5,  3;
%e A302248    9,  0,  0,  9;
%e A302248    6,  6,  0,  0;
%e A302248   28,  0,  0,  0;
%e A302248    7,  7,  0,  0;
%e A302248   12,  0,  0, 12;
%e A302248    8,  8,  8,  0,  0;
%e A302248   31,  0,  0,  0,  0;
%e A302248    9,  9,  0,  0,  0;
%e A302248   39,  0,  0,  0,  0;
%e A302248   10, 10,  0,  0,  0;
%e A302248   42,  0,  0,  0,  0;
%e A302248   11, 11,  5,  0,  0,  5;
%e A302248   18,  0,  0, 18,  0,  0;
%e A302248   12, 12,  0,  0,  0,  0;
%e A302248   60,  0,  0,  0,  0,  0;
%e A302248   13, 13,  0,  0,  5,  0;
%e A302248   21,  0,  0, 21,  0,  0;
%e A302248   14, 14,  6,  0,  0,  6;
%e A302248   56,  0,  0,  0,  0,  0,  0;
%e A302248 ...
%e A302248 For n = 21 the 21st row of A299778 is [11, 5, 0, 5, 0, 11], so the 21st row of this triangle is [11, 11, 5, 0, 0, 5].
%Y A302248 Row sums give A000203.
%Y A302248 Row n has length A003056(n).
%Y A302248 Column k starts in row A000217(k).
%Y A302248 The number of nonzero terms in row n is A237271(n).
%Y A302248 Column 1 is A241838.
%Y A302248 The triangle with n rows contain A237590(n) nonzero terms.
%Y A302248 Cf. A280850 (analog for subparts).
%Y A302248 Cf. A196020, A235791, A236104, A237048, A237270, A237591, A237593, A239660, A240542, A244050, A245092, A262626, A279387, A279388, A280851, A299778.
%K A302248 nonn,tabf
%O A302248 1,2
%A A302248 _Omar E. Pol_, Apr 10 2018