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A095026 Lower triangle T(j,k) read by rows, where T(j,k) is the number of occurrences of the digit k-1 as least significant digit in the base-j multiplication table.

%I A095026 #9 Jun 19 2015 08:11:55
%S A095026 1,3,1,5,2,2,8,2,4,2,9,4,4,4,4,15,2,6,5,6,2,13,6,6,6,6,6,6,20,4,8,4,
%T A095026 12,4,8,4,21,6,6,12,6,6,12,6,6,27,4,12,4,12,9,12,4,12,4,21,10,10,10,
%U A095026 10,10,10,10,10,10,10,40,4,8,10,16,4,20,4,16,10,8,4,25,12,12,12,12,12,12,12
%N A095026 Lower triangle T(j,k) read by rows, where T(j,k) is the number of occurrences of the digit k-1 as least significant digit in the base-j multiplication table.
%C A095026 Sum_{k=1..j} T(j,k) = j^2.
%C A095026 Assumes a suitable continuation of the representation of digits in bases 11, 12 (9,A,B,..)
%H A095026 David Book, <a href="http://pleacher.com/mp/probweek/p2001/a012201.html">The Multiplying Digits Problem.</a>
%e A095026 a(2)=T(2,1)=3 because 3 of the 4 possible combinations of last digits in the
%e A095026 product of two binary numbers produce 0 as last digit of the result. a(3)=T(2,2)=1 because only ...1 * ...1 gives a result with last digit=1.
%e A095026 T(10,k)={27,4,12,4,12,9,12,4,12,4} gives the probability in percent (j^2=100) to get {0,1,2,...,9} as last decimal digit in the decimal representation of the product of two arbitrary integers.
%Y A095026 The first column T(n, 1)=A018804(n).
%K A095026 nonn,tabl,base
%O A095026 1,2
%A A095026 _Hugo Pfoertner_, Jun 02 2004
%E A095026 More terms from _David Wasserman_, Jun 03 2004