



1, 4, 7, 7, 10, 13, 10, 13, 16, 19, 13, 16, 19, 22, 25, 16, 19, 22, 25, 28, 31, 19, 22, 25, 28, 31, 34, 37, 22, 25, 28, 31, 34, 37, 40, 43, 25, 28, 31, 34, 37, 40, 43, 46, 49, 28, 31, 34, 37, 40, 43, 46, 49, 52, 55, 31, 34, 37, 40, 43, 46, 49, 52, 55, 58, 61, 34, 37, 40, 43, 46, 49, 52, 55, 58, 61, 64, 67
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OFFSET

0,2


COMMENTS

Left border = A016777, (1, 4, 7, 10, 13, ...).
Right border = A016921: (1, 7, 13, 19, 25, ...).
Row sums = A051682, 11gonal numbers: (1, 11, 30, 58, 95, ...).


LINKS



EXAMPLE

First few rows of the triangle:
1;
4, 7;
7, 10, 13;
10, 13, 16, 19;
13, 16, 19, 22, 25;
16, 19, 22, 25, 28, 31;
19, 22, 25, 28, 31, 34, 37;
...


CROSSREFS



KEYWORD



AUTHOR



EXTENSIONS

a(28) ff. corrected and more terms from Georg Fischer, Jun 05 2023


STATUS

approved



