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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 (list; graph; refs; listen; history; text; internal format)
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.
LINKS
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 *)
CROSSREFS
Sequence in context: A179760 A334852 A160552 * A006257 A323555 A323553
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

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Last modified April 25 06:14 EDT 2024. Contains 371964 sequences. (Running on oeis4.)