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Number of numbers i in the range 1 <= i <= n such that there is a number j in the range 1 <= j <= n for which the carryless product i*j equals n.
5

%I #7 Mar 30 2012 17:38:11

%S 1,2,2,3,5,6,2,10,4,2,2,2,2,2,2,2,2,2,2,8,2,8,2,8,2,10,2,10,2,4,4,4,4,

%T 4,4,4,4,4,4,18,4,18,4,18,4,20,4,20,4,50,2,2,4,4,54,6,6,8,8,36,6,36,6,

%U 36,6,38,6,38,6,12,12,12,12,12,12,12,12,12,12,50,8,50,8,50,8,52,8,52,8,16

%N Number of numbers i in the range 1 <= i <= n such that there is a number j in the range 1 <= j <= n for which the carryless product i*j equals n.

%C Counted with multiplicity.

%H <a href="/index/Ca#CARRYLESS">Index entries for sequences related to carryless arithmetic</a>

%Y Cf. A000005, A169892, A169893, A169987-A169899.

%K nonn,base

%O 1,2

%A _David Applegate_, _Marc LeBrun_ and _N. J. A. Sloane_, Jul 06 2010