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A256263
Triangle read by rows: T(j,k) = 2*k-1 if k is a power of 2, otherwise, between positions that are powers of 2 we have the initial terms of A016969, with j>=0, 1<=k<=A011782(j) and T(0,1) = 0.
8
0, 1, 1, 3, 1, 3, 5, 7, 1, 3, 5, 7, 5, 11, 17, 15, 1, 3, 5, 7, 5, 11, 17, 15, 5, 11, 17, 23, 29, 35, 41, 31, 1, 3, 5, 7, 5, 11, 17, 15, 5, 11, 17, 23, 29, 35, 41, 31, 5, 11, 17, 23, 29, 35, 41, 47, 53, 59, 65, 71, 77, 83, 89, 63, 1, 3, 5, 7, 5, 11, 17, 15, 5, 11, 17, 23, 29, 35, 41, 31, 5, 11, 17, 23, 29, 35, 41, 47, 53, 59, 65, 71, 77, 83, 89
OFFSET
0,4
COMMENTS
Partial sums give A256264.
First differs from A160552 at a(27).
Appears to be a canonical sequence partially related to the cellular automata of A139250, A147562, A162795, A169707, A255366, A256250. See also A256264 and A256260.
EXAMPLE
Written as an irregular triangle in which the row lengths are the terms of A011782, the sequence begins:
0;
1;
1,3;
1,3,5,7;
1,3,5,7,5,11,17,15;
1,3,5,7,5,11,17,15,5,11,17,23,29,35,41,31;
1,3,5,7,5,11,17,15,5,11,17,23,29,35,41,31,5,11,17,23,29,35,41,47,53,59,65,71,77,83,89,63;
...
Right border gives A000225.
Apart from the initial 0 the row sums give A000302.
Rows converge to A256258.
.
Illustration of initial terms in the fourth quadrant of the square grid:
---------------------------------------------------------------------------
n a(n) Compact diagram
---------------------------------------------------------------------------
0 0 _
1 1 |_|_ _
2 1 |_| |
3 3 |_ _|_ _ _ _
4 1 |_| | | |
5 3 |_ _| | |
6 5 |_ _ _| |
7 7 |_ _ _ _|_ _ _ _ _ _ _ _
8 1 |_| | | |_ _ | |
9 3 |_ _| | |_ | | |
10 5 |_ _ _| | | | | |
11 7 |_ _ _ _| | | | |
12 5 | | |_ _ _| | | |
13 11 | |_ _ _ _ _| | |
14 17 |_ _ _ _ _ _ _| |
15 15 |_ _ _ _ _ _ _ _|_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
16 1 |_| | | |_ _ | |_ _ _ _ _ _ | |
17 3 |_ _| | |_ | | |_ _ _ _ _ | | |
18 5 |_ _ _| | | | | |_ _ _ _ | | | |
19 7 |_ _ _ _| | | | |_ _ _ | | | | |
20 5 | | |_ _ _| | | |_ _ | | | | | |
21 11 | |_ _ _ _ _| | |_ | | | | | | |
22 17 |_ _ _ _ _ _ _| | | | | | | | | |
23 15 |_ _ _ _ _ _ _ _| | | | | | | | |
24 5 | | | | | | |_ _ _| | | | | | | |
25 11 | | | | | |_ _ _ _ _| | | | | | |
26 17 | | | | |_ _ _ _ _ _ _| | | | | |
27 23 | | | |_ _ _ _ _ _ _ _ _| | | | |
28 29 | | |_ _ _ _ _ _ _ _ _ _ _| | | |
29 35 | |_ _ _ _ _ _ _ _ _ _ _ _ _| | |
30 41 |_ _ _ _ _ _ _ _ _ _ _ _ _ _ _| |
31 31 |_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _|
.
a(n) is also the number of cells in the n-th region of the diagram.
A256264(n) gives the total number of cells after n-th stage.
MATHEMATICA
Flatten@Join[{0}, NestList[Join[#, Range[Length[#] - 1]*6 - 1, {2 #[[-1]] + 1}] &, {1}, 6]] (* Ivan Neretin, Feb 14 2017 *)
KEYWORD
nonn,tabf,look
AUTHOR
Omar E. Pol, Mar 30 2015
EXTENSIONS
Terms a(95) to a(98) fixed by Ivan Neretin, Feb 14 2017
STATUS
approved