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This sequence splices 36x^2 - 810x + 2753 and the first of its transforms 9x^2 - 423x + 3167 into a prime chain 91 terms long.
0

%I #5 Jan 17 2013 03:37:53

%S 3167,2753,2753,1979,2357,1277,1979,647,1619,89,1277,397

%N This sequence splices 36x^2 - 810x + 2753 and the first of its transforms 9x^2 - 423x + 3167 into a prime chain 91 terms long.

%o (Pascal) procedure Ndegrees; var a : array[0..16] of extended; aa, ct,bb,cc: longint; n,nh,i,j : integer; ab1,ab2 : extended; begin for i := 0 to 16 do a[i] := 0; N := 7; a[0] := 3167{ FIRST TERM OF PRIME CHAIN}; nh := 1; a[1] := 2753 ;a[2] := 2753 ;a[3] := 1979 ;a[4] := 2357 ;a[5] := 1277 ;a[6] := 1979 ; a[7] := 647 ;a[8] := 1619 ; repeat for i := N downto nh do BEGIN a[i] := a[i] - a[i-1] ; IF NH = 5 THEN A[I] := ABS(A[I]); {******} END; nh := nh + 1; until nh = n + 2; ct := 0; repeat ct := ct + 1; ab1 := a[n] + a[n-1]; for i := N-1 downto 1 do begin IF I = 5 THEN IF ODD(ct) THEN A[i] := -A[i];{******} ab2 := a[i] + a[i-1] ; a[i] := ab1; ab1 := ab2; end; WRITELN(AB1); READLN; until 1<0; END;

%Y Cf. A140755.

%K nonn,uned

%O 1,1

%A Aldrich Stevens (aldrichstevens(AT)msn.com), May 29 2008