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Triangle read by rows: T(1,1) = 1; T(n+1,k) = T(n,k+1), 1 <= k < n; T(n+1,n) = 2*T(n,1); T(n+1,n+1) = 2*T(n,1) - 1.
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%I #11 Apr 15 2014 02:27:48

%S 1,2,1,1,4,3,4,3,2,1,3,2,1,8,7,2,1,8,7,6,5,1,8,7,6,5,4,3,8,7,6,5,4,3,

%T 2,1,7,6,5,4,3,2,1,16,15,6,5,4,3,2,1,16,15,14,13,5,4,3,2,1,16,15,14,

%U 13,12,11,4,3,2,1,16,15,14,13,12,11,10,9,3,2

%N Triangle read by rows: T(1,1) = 1; T(n+1,k) = T(n,k+1), 1 <= k < n; T(n+1,n) = 2*T(n,1); T(n+1,n+1) = 2*T(n,1) - 1.

%C Let h be the initial term of row n, to get row n+1, remove h and then append 2*h and 2*h+1;

%C A080079(n) = T(n,1); T(n,T(n,1)) = 1.

%H Reinhard Zumkeller, <a href="/A240769/b240769.txt">Rows n = 1..128 of triangle, flattened</a>

%e . 1: 1

%e . 2: 2 1

%e . 3: 1 4 3

%e . 4: 4 3 2 1

%e . 5: 3 2 1 8 7

%e . 6: 2 1 8 7 6 5

%e . 7: 1 8 7 6 5 4 3

%e . 8: 8 7 6 5 4 3 2 1

%e . 9: 7 6 5 4 3 2 1 16 15

%e . 10: 6 5 4 3 2 1 16 15 14 13

%e . 11: 5 4 3 2 1 16 15 14 13 12 11

%e . 12: 4 3 2 1 16 15 14 13 12 11 10 9 .

%o (Haskell)

%o a240769 n k = a240769_tabl !! (n-1) !! (k-1)

%o a240769_row n = a240769_tabl !! (n-1)

%o a240769_tabl = iterate (\(x:xs) -> xs ++ [2*x, 2*x-1]) [1]

%Y Cf. A062383 (row maxima).

%K nonn,tabl,look

%O 1,2

%A _Reinhard Zumkeller_, Apr 13 2014