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A171239 Triangle read by rows extracted from convolution product (1,2,3,...) * A002865: (1,1,2,2,4,4,7,8,...) 2
1, 1, 2, 2, 2, 3, 2, 4, 3, 4, 4, 4, 6, 4, 5, 4, 8, 6, 8, 5, 6, 7, 8, 12, 8, 10, 6, 7, 8, 14, 12, 16, 10, 12, 7, 8, 8, 14, 12, 16, 10, 12, 7, 8, 12, 16, 21, 16, 20, 12, 14, 8, 9, 14, 24, 24, 28, 20, 24, 14, 10, 9, 10 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Row sums = A058682 starting (1, 3, 7, 13, 23, 37, 58, 87,...).
LINKS
FORMULA
Triangle read by rows, ascending diagonals of an array formed by the product of
(1,2,3,...) and (1,1,2,2,4,4,7,8,12,...).
EXAMPLE
The triangle = upward sloping diagonals of multiplication table:
.
1,..2,..3,..4,..5,..6,..7,...
1,..2,..3,..4,..5,..6,..7,...
2,..4,..6,..8,.10,.12,.14,...
2,..4,..6,..8,.10,.12,.14,...
... First few rows of the triangle =
.
1;
1, 2;
2, 2, 3;
2, 4, 3, 4;
4, 4, 6, 4, 5;
4, 8, 6, 8, 5, 6;
7, 8, 12, 8, 10, 6, 7;
8, 14, 12, 16, 10, 12, 7, 8;
12, 16, 21, 16, 20, 12, 14, 8, 9;
14, 24, 24, 28, 20, 24, 14, 10, 9, 10;
21, 28, 36, 32, 35, 24, 28, 16, 18, 10, 11;
24, 42, 42, 48, 40, 42, 28, 32, 18, 20, 11, 12;
34, 48, 63, 56, 60, 48, 49, 32, 36, 20, 22, 12, 13;
41, 68, 72, 84, 70, 72, 56, 56, 36, 40, 22, 24, 13, 14;
...
CROSSREFS
Sequence in context: A125749 A014085 A248891 * A029210 A321909 A346598
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Dec 05 2009
STATUS
approved

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Last modified April 14 10:04 EDT 2024. Contains 371657 sequences. (Running on oeis4.)