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A152204
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Triangle read by rows: T(n,k) = 2n-4k+5 (n >= 0, 1 <=k <= 1+floor(n/2)).
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4
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1, 3, 5, 1, 7, 3, 9, 5, 1, 11, 7, 3, 13, 9, 5, 1, 15, 11, 7, 3, 17, 13, 9, 5, 1, 19, 15, 11, 7, 3, 21, 17, 13, 9, 5, 1, 23, 19, 15, 11, 7, 3, 25, 21, 17, 13, 9, 5, 1, 27, 23, 19, 15, 11, 7, 3, 29, 25, 21, 17, 13, 9, 5, 1, 31, 27, 23, 19, 15, 11, 7, 3, 33
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| All terms are odd, decreasing across rows. Row sums = A000217, the triangular numbers.
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LINKS
| Nathaniel Johnston, Table of n, a(n) for n = 1..10000
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FORMULA
| By columns, odd terms in every column, n-th column starts at row (2n-1).
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EXAMPLE
| First few rows of the triangle =
1
3
5 1
7 3
9 5 1
11 7 3
13 9 5 1
15 11 7 3
17 13 9 5 1
19 15 11 7 3
21 17 13 9 5 1
...
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MAPLE
| T := proc(n, k) return 2*n-4*k+5: end: seq(seq(T(n, k), k=1..1+floor(n/2)), n=0..20); # Nathaniel Johnston, May 01 2011
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CROSSREFS
| Cf. A000217.
Sequence in context: A133045 A158858 A202356 * A114216 A086233 A065395
Adjacent sequences: A152201 A152202 A152203 * A152205 A152206 A152207
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KEYWORD
| nonn,tabf,easy
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AUTHOR
| Gary W. Adamson (qntmpkt(AT)yahoo.com), Nov 29 2008
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EXTENSIONS
| Edited by N. J. A. Sloane, Sep 25 2010, following a suggestion from Emeric Deutsch
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