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%I #8 Aug 10 2020 11:12:10
%S 1,1,1,1,1,2,2,1,1,1,1,3,4,3,2,1,1,2,4,7,7,5,3,1,1,1,1,3,6,11,14,12,8,
%T 4,2,1,1,2,4,9,17,25,26,20,12,6,3,1,1,1,1,3,6,13,26,42,51,46,32,18,9,
%U 4,2,1,1,2,4,9,19,39,68,93,97,78,50,27,13,6,3,1,1
%N Triangle (read by rows) where the number of row entries increases by steps of 2 and the entries are stacked in a rectangular fashion. The end entries are set to 1. Rest of entries are set to the sum of the entry directly above in the previous row plus the entry (if present) in the previous row that is either to the left (if the current row number is even) or to the right (if odd).
%C The row sums are 2^n-1 (A000225). Shares many entries with A027926., e.g. the 'central column' (and greatest numbers in the rows) is A027988 (Greatest number in row n of array T given by A027926.)
%e ........................1........................
%e .....................1..1..1.....................
%e ..................1..2..2..1..1..................
%e ...............1..1..3..4..3..2..1...............
%e ............1..2..4..7..7..5..3..1..1............
%e .........1..1..3..6.11.14.12..8..4..2..1.........
%e ......1..2..4..9.17.25.26.20.12..6..3..1..1......
%e ...1..1..3..6.13.26.42.51.46.32.18..9..4..2..1...
%e 1..2..4..9.19.39.68.93.97.78.50.27.13..6..3..1..1
%Y Cf. A000225, A027926, A027988.
%K nonn,tabf
%O 1,6
%A _Gerald McGarvey_, Aug 14 2004
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