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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

%I

%S 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,

%T 9,9,8,10,10,10,10,10,12,11,9,12,11,11,14,10,14,14,13,14,13,13,14,16,

%U 15,13,16,15,17,17,15,18,14,17,16,19,18,19,15,20,19,18,20,20,18,20,21,22

%N 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.

%e Triangle begins

%e 1 (0 abundant)

%e 2 3 (0 abundant)

%e 4 5 6 (0 abundant)

%e 7 8 9 10 (0 abundant)

%e 11 12 13 14 15 (1 abundant)

%e 16 17 18 19 20 21 (2 abundant)

%e 22 23 24 25 26 27 28 (1 abundant)

%Y Cf. A005101.

%K easy,nonn

%O 1,6

%A _Jason Earls_, Jun 08 2003

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Last modified July 13 15:18 EDT 2020. Contains 335688 sequences. (Running on oeis4.)