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A084840 Write the numbers 1, 2, ... in a triangle with n terms in the n-th row; a(n) = number of abundant integers in n-th row. 1
0, 0, 0, 0, 1, 2, 1, 2, 2, 2, 3, 3, 4, 4, 4, 2, 4, 4, 4, 7, 5, 4, 6, 5, 7, 6, 8, 7, 6, 9, 7, 8, 9, 8, 9, 9, 8, 10, 10, 10, 10, 10, 12, 11, 9, 12, 11, 11, 14, 10, 14, 14, 13, 14, 13, 13, 14, 16, 15, 13, 16, 15, 17, 17, 15, 18, 14, 17, 16, 19, 18, 19, 15, 20, 19, 18, 20, 20, 18, 20, 21, 22 (list; graph; refs; listen; history; internal format)
OFFSET

1,6

EXAMPLE

Triangle begins

1 (0 abundant)

2 3 (0 abundant)

4 5 6 (0 abundant)

7 8 9 10 (0 abundant)

11 12 13 14 15 (1 abundant)

16 17 18 19 20 21 (2 abundant)

22 23 24 25 26 27 28 (1 abundant)

CROSSREFS

Cf. A005101.

Sequence in context: A070096 A024154 A117875 * A029278 A125950 A052954

Adjacent sequences:  A084837 A084838 A084839 * A084841 A084842 A084843

KEYWORD

easy,nonn

AUTHOR

Jason Earls (zevi_35711(AT)yahoo.com), Jun 08 2003

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Last modified February 14 11:36 EST 2012. Contains 205623 sequences.