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%I #2 Mar 31 2012 13:23:39
%S 1,2,1,5,4,2,9,8,6,2,17,16,14,9,3,28,27,25,20,12,3,47,46,44,39,30,16,
%T 4,73,72,70,65,56,40,20,4,114,113,111,106,97,80,55,25,5,170,169,167,
%U 162,153,136,109,70,30,5,253,252,250,245,236,219,191,147,91,36,6,365
%N Convolve A008619 with sequences which map to 2,3,5,7,11,13,17... A000040 then, by bending when needed, summarize the results in a triangular array.
%C Sequence A164680 is not in the triangle since 45 = 3*15 and 15 is not a member of A000040 (the prime numbers).
%e The desired triangle begins:
%e .1
%e .2..1
%e .5..4..2
%e .9..8..6..2
%e 17.16.14..9..3
%e 28.27.25.20.12..3
%e 47.46.44.39.30.16..4
%e etc.
%e Note that 21 = 3*7 maps to 1,2,5,9,17,27,44,... A139672 is embedded in the triangle.
%Y Cf. A008619 A002620 A006918 A097701 A139672 ... A000097 (embedded sequences).
%K nonn,tabl,uned
%O 1,2
%A _Alford Arnold_, Aug 25 2009