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%I #12 Apr 15 2014 02:50:50
%S 35,25,49,65,77,143,55,91,121,169,95,119,209,221,323,65,133,187,247,
%T 289,361,125,161,275,299,425,437,575,115,175,253,325,391,475,529,625,
%U 155,203,341,377,527,589,713,725,899,145,217,319,403,493,569,667,775,841
%N Alternating triangle (version 2) read by rows: composites k such that k=6*m-+1=r*j r>=j and n>=q>0 where r=6*n-1 or r=6*n+1 and j=6*q-1 or j=6*q+1.
%C Composites of form 6*m-1 are in even (0,2,4,..) rows of alternating triangle only. Composites of form 6*m+1 are in odd (1,3,5,..) rows of alternating triangle only. 1 UNION nontrivial primes UNION A174027(without repetition) = A140475 U A174027(without repetition) = A007310 = numbers of form 6*n+-1, where alternating triangle (version 1) is A173865.
%e Triangle begins:
%e 35(=7*5) in even 0th row;
%e 25(=5*5) and 49(=7*7) in odd 1st row;
%e 65(=13*5), 77(=11*7) and 143(=13*11) in even 2nd row.
%Y Cf. A007310, A140475, A173825, A173865.
%K nonn,tabl,uned
%O 1,1
%A _Juri-Stepan Gerasimov_, Mar 06 2010, Mar 17 2010
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