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Irregular triangle read by rows in which row n lists the print order of a 4n-page booklet.
1

%I #36 Apr 02 2023 12:47:39

%S 2,3,4,1,2,7,8,1,4,5,6,3,2,11,12,1,4,9,10,3,6,7,8,5,2,15,16,1,4,13,14,

%T 3,6,11,12,5,8,9,10,7,2,19,20,1,4,17,18,3,6,15,16,5,8,13,14,7,10,11,

%U 12,9,2,23,24,1,4,21,22,3,6,19,20,5,8,17,18,7,10,15,16,9,12,13,14,11

%N Irregular triangle read by rows in which row n lists the print order of a 4n-page booklet.

%C Row n is a permutation of the first 4*n positive integers.

%H Alois P. Heinz, <a href="/A361258/b361258.txt">Rows n = 1..100, flattened</a>

%e Triangle begins:

%e 2, 3, 4, 1;

%e 2, 7, 8, 1, 4, 5, 6, 3;

%e 2, 11, 12, 1, 4, 9, 10, 3, 6, 7, 8, 5;

%e 2, 15, 16, 1, 4, 13, 14, 3, 6, 11, 12, 5, 8, 9, 10, 7;

%e ...

%p T:= n-> seq([2*m, 4*n-2*m+1, 4*n-2*m+2, 2*m-1][], m=1..n):

%p seq(T(n), n=1..6); # _Alois P. Heinz_, Mar 06 2023

%Y Cf. A008586 (row lengths), A033585 (row sums).

%K nonn,look,tabf

%O 1,1

%A _Ole Palnatoke Andersen_, Mar 06 2023