Search: id:A093682 Results 1-1 of 1 results found. %I A093682 %S A093682 1,2,1,4,3,1,5,4,4,1,10,6,5,7,1,11,10,8,8,10,1,13,12,10,10,11,19,1,14, %T A093682 13,13,11,13,20,28,1,28,15,14,16,14,22,29,55,1,29,28,17,17,20,23,31,56, %U A093682 82,1,31,30,28,20,22,28,32,58,83,163,1,32,31,31,28,23,29,37,59,85 %N A093682 Array T(m,n) by antidiagonals: nonarithmetic-3-progression sequences with simple closed forms. %C A093682 The nonarithmetic-3-progression sequences starting with a(1)=1, a(2)=1+3^m or 1+2*3^m, m>=0, seem to have especially simple 'closed' forms. None of these formulae have been proved, however. %C A093682 T(m,1)=1, T(m,2) = 1+(1+[m even])*3^[m/2] = 1+A038754(m), m>=0, n>0; T(m,n) is least k such that no three terms of T(m,1),T(m,2),...,T(m, n-1),k form an arithmetic progression. %H A093682 Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics. %F A093682 T(m, n) = sum[k=1, n-1, (3^A007814(k)+1)/2] + f(n), with f(n) a P-periodic function, where P <= 2^[(m+3)/2] (conjectured and checked up to m=13, n=1000). %F A093682 The formula implies that T(m, n)=b(n-1) where b(2n)=3b(n)+p(n), b(2n+1)=3b(n)+q(n), with p, q sequences generated by rational o.g.f.s. %e A093682 1 2 4 5 10 11 13 ... %e A093682 1 3 4 6 10 12 13 ... %e A093682 1 4 5 8 10 13 14 ... %e A093682 1 7 8 10 11 16 17 ... %e A093682 1 10 11 13 14 20 22 ... %Y A093682 Rows 0-6 are A003278, A004793, A033157, A093678, A093679, A093680, A093681. %Y A093682 Column 2 is 1+A038754. Cf. A092482, A033158. %Y A093682 Sequence in context: A132280 A059970 A112157 this_sequence A134543 A093010 A093966 %Y A093682 Adjacent sequences: A093679 A093680 A093681 this_sequence A093683 A093684 A093685 %K A093682 nonn,tabl %O A093682 0,2 %A A093682 Ralf Stephan (ralf(AT)ark.in-berlin.de), Apr 09 2004 Search completed in 0.001 seconds