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A126696 Tenth-squares: floor(n/10)*ceiling(n/10). 0
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 6, 6, 6, 6, 6, 6, 6, 6, 6, 9, 12, 12, 12, 12, 12, 12, 12, 12, 12, 16, 20, 20, 20, 20, 20, 20, 20, 20, 20, 25, 30, 30, 30, 30, 30, 30, 30, 30, 30, 36, 42, 42, 42, 42, 42, 42, 42, 42, 42, 49, 56, 56, 56, 56, 56, 56, 56, 56, 56 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,12

LINKS

Table of n, a(n) for n=0..79.

FORMULA

Equivalently, floor(n^2/100).

MATHEMATICA

f[n_]:=Module[{c=n/10}, Floor[c]Ceiling[c]]; f[Range[0, 90]] (* Harvey P. Dale, Apr 04 2011 *)

PROG

(MAGMA) [ Floor(n/10)*Ceiling(n/10) : n in [0..100]];

CROSSREFS

Cf. A002620, A024206, A072280, A002984, A007590, A000212, A118015, A056827, A118013.

Sequence in context: A237975 A032574 A058515 * A244464 A250201 A252375

Adjacent sequences:  A126693 A126694 A126695 * A126697 A126698 A126699

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, May 27 2007

STATUS

approved

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Last modified November 19 16:10 EST 2017. Contains 294936 sequences.