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%I #5 Apr 13 2013 08:27:31
%S 5,1,25,11,35,77,7,55,49,121,17,65,119,143,221,13,85,91,181,109,289,
%T 23,95,161,209,299,323,437,19,115,133,253,247,391,361,529,29,125,203,
%U 275,377,425,551,575,725,25,145,175,319,325,493,475,667,625,841,35,185,245
%N Alternating triangle (version 3) read by rows: numbers k such that k=6*m+3-+2=r*j , r>=j and n>=q where r=6*n+3-2 or r=6*n+3+2 and j=6*q+3-2 or j=6*q+3+2.
%C Numbers of form 6*m+3+2 are in even rows, numbers of form 6*m+3-2 are in odd rows. Numbers of alternating triangle (version 1) are A173865. Numbers of alternating triangle (version 2) are A174027.
%e Triangle begins: 5*1 1*1 5*5 11*1 7*5 11*7 7*1 11*5 7*7 11*11 17*1 13*5 17*7 13*11 17*13 13*1 17*5 13*7 17*11 13*13 17*17.. or 5(in even 0 row) 1 25(in odd 1 row) 11 35 77(in even 2 row) 7 55 49 121(in odd 3 row) 17 65 119 143 221(in even 4 row) 13 85 91 181 169 289(in odd 5 row)..
%e That is:
%e 5;
%e 1, 25;
%e 11, 35, 77;
%e 7, 55, 49, 121;
%e 17, 65, 119, 143;
%Y Cf. A007310, A173825, A173865, A174027.
%K nonn,tabl
%O 1,1
%A _Juri-Stepan Gerasimov_, Mar 17 2010, Mar 30 2010
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