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A181109 Array whose rows result from iterating an algorithm that takes (1,1,1,1,...) to (1,3,5,7,...). 0
1, 1, 1, 1, 3, 1, 1, 5, 3, 1, 1, 7, 4, 3, 1, 1, 9, 5, 4, 3, 1, 1, 11, 7, 5, 4, 3, 1, 1, 13, 8, 7, 5, 4, 3, 1, 1, 15, 10, 9, 7, 5, 4, 3, 1, 1, 17, 11, 11, 9, 7, 5, 4, 3, 1, 1, 19, 13, 12, 11, 9, 7, 5, 4, 3, 1, 1, 21, 14, 13, 12, 11, 9, 7, 5, 4, 3, 1, 1, 23, 15, 15, 13, 13, 11, 9, 7, 5, 4, 3, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Row 1: A000012 (constant sequence of 1's)

Row 2: A005408 (odd positive integers)

Row 3: A136119

limit-row: A003159

LINKS

Table of n, a(n) for n=1..91.

FORMULA

To generate row n+1 from row n, let

(row n) = (s(1), s(2), s(3), ...)

(row n+1) = (t(1), t(2), t(3), ...)

Then for k=1,2,3,..., let

t(k) = least positive integer not yet in sequences t or u

u(k) = t(k) + s(k).

EXAMPLE

Northwest corner:

1...1...1...1...1....1...1....1....1...

1...3...5...7...9...11...13...15...17...

1...3...4...5...7...8....10...11...13...

1...3...4...5...7...9....11...12...13...

CROSSREFS

Cf. A005408, A136119, A003159, A181108.

Sequence in context: A174609 A280533 A229288 * A152720 A131247 A114278

Adjacent sequences:  A181106 A181107 A181108 * A181110 A181111 A181112

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Oct 03 2010

STATUS

approved

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Last modified October 16 11:51 EDT 2019. Contains 328056 sequences. (Running on oeis4.)