A240769 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.

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

Offset

1,2

Comments

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;

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

Links

Reinhard Zumkeller, Rows n = 1..128 of triangle, flattened

Example

.   1:   1
.   2:   2   1
.   3:   1   4   3
.   4:   4   3   2   1
.   5:   3   2   1   8   7
.   6:   2   1   8   7   6   5
.   7:   1   8   7   6   5   4   3
.   8:   8   7   6   5   4   3   2   1
.   9:   7   6   5   4   3   2   1  16  15
.  10:   6   5   4   3   2   1  16  15  14  13
.  11:   5   4   3   2   1  16  15  14  13  12  11
.  12:   4   3   2   1  16  15  14  13  12  11  10   9 .

Prog

(Haskell)
a240769 n k = a240769_tabl !! (n-1) !! (k-1)
a240769_row n = a240769_tabl !! (n-1)
a240769_tabl = iterate (\(x:xs) -> xs ++ [2*x, 2*x-1]) [1]

Crossrefs

Cf. A062383 (row maxima).

Sequence in context: A225924 A078015 A366781 * A357320 A174455 A245596

Adjacent sequences: A240766 A240767 A240768 * A240770 A240771 A240772

Keyword

nonn,tabl,look

Author

Reinhard Zumkeller, Apr 13 2014

Status

approved