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A062896
Number of addition triangles with apex n (version 2).
8
1, 2, 2, 4, 4, 7, 7, 12, 12, 18, 19, 27, 28, 39, 41, 54, 58, 74, 78, 99, 106, 129, 139, 168, 179, 214, 229, 268, 289, 335, 357, 414, 443, 504, 540, 612, 653, 737, 786, 878, 938, 1045, 1111, 1234, 1313, 1444, 1539, 1692, 1795, 1965, 2082, 2273, 2414
OFFSET
1,2
COMMENTS
An addition triangle has any set of positive numbers as base; other rows are formed by adding pairs of adjacent numbers.
Reversing the base does not count as a different triangle.
LINKS
EXAMPLE
For n = 5:
5
2,3 5 5
1,1,2 4,1 2,3 5.
with four different bases, so a(5) = 4.
CROSSREFS
See A062684 for version 1 (counts reversals).
Equivalent sequences with restrictions on rows: A337765 (weakly increasing), A337766 (strongly increasing).
Equivalent sequence where n is the sum of all numbers in the triangle: A337787.
Sequence in context: A266776 A371514 A363214 * A025065 A306664 A365826
KEYWORD
easy,nonn
AUTHOR
Naohiro Nomoto, Feb 11 2002
EXTENSIONS
Extended and edited by John W. Layman, Feb 14 2002
STATUS
approved