|
%I #20 Feb 05 2018 22:01:55
%S 4,8,10,16,38,18,110,22,220,350,406,28,40,190,252,148,442,504,34,440,
%T 946,254,1892,250,5434,2860,290,3640,14014,7150,46,616,6380,16604,
%U 11284,55432,74074,27170,52,428,8228,22984,50456,89284,129506,155584
%N Distinct even numbers in the numerators of the 1/3-Pascal triangle (by row).
%H Peter J. C. Moses, <a href="/A046559/b046559.txt">Table of n, a(n) for n = 1..10000</a>
%e 1/1; -->
%e 1/1 1/1; -->
%e 1/1 1/3 1/1; -->
%e 1/1 4/3 4/3 1/1; --> 4
%e 1/1 7/3 8/3 7/3 1/1; --> 8
%e 1/1 10/3 5/1 5/1 10/3 1/1; --> ...
%e 1/1 13/3 25/3 10/1 25/3 13/3 1/1;
%e 1/1 16/3 38/3 55/3 55/3 38/3 16/3 1/1; ...
%t thirdPascal[1]={1}; thirdPascal[2]={1,1}; thirdPascal[3]={1,1/3,1}; thirdPascal[n_] := thirdPascal[n] = Join[{1}, Map[Total, Partition[thirdPascal[n-1], 2, 1]], {1}]; DeleteDuplicates[Flatten[Table[Select[Numerator[thirdPascal[n]], EvenQ], {n, 20}]]]
%Y Cf. A046534.
%K tabf,nonn,look,less
%O 1,1
%A _Mohammad K. Azarian_
%E Terms a(12) and beyond from b-file by _Andrew Howroyd_, Feb 05 2018
|
