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Search: id:A140125
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| A140125 |
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This is a prime chain of 147 terms consisting of the output of four equations that alternate sequentially. The equations are either subsequences of x^2 - 79x + 1601 or transforms. The four equations are : 4x^2 -146x +1373, 4x^2 -144x + 1459, 4x^2 -142x + 1301, 4x^2 -140x + 1877. |
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+0 1
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| 1373, 1459, 1301, 1877, 1231, 1319, 1163, 1741, 1097, 1187, 1033, 1613
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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It may be possible to generate prime chains of any arbitrary length using minor variations of the procedure below.
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PROGRAM
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This Pascal procedure can probably be imported into Borland's latest programming software, and run without any changes: procedure Ndegrees3; var a : array[0..16] of extended; ct: longint; n, nh, i, j : integer; ab1, ab2 : extended; begin for i := 0 to 16 do a[i] := 0; N := 5; a[0] := 1373{ FIRST TERM OF PRIME CHAIN}; writeln('1'); writeln(trunc(a[0])); writeln; nh := 1; a[1] := 1459 ; a[2] := 1301 ; a[3] := 1877 ; a[4] := 1231 ; a[5] := 1319 ; repeat for i := N downto nh do begin a[i] := a[i] - a[i-1] ; IF NH = 3 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 ab2 := a[i] + a[i-1] ; a[i] := ab1; ab1 := ab2; end; IF ODD(ct + 1) THEN A[5] := -A[5]; {******} A[3] := -A[3]; {******} a[0] := ab1; writeln(ct + 1); writeln(trunc(a[0])); {} readln; until 1<0; END;
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CROSSREFS
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Sequence in context: A135819 A139414 A060981 this_sequence A069490 A045131 A056049
Adjacent sequences: A140122 A140123 A140124 this_sequence A140126 A140127 A140128
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KEYWORD
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nonn,uned
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AUTHOR
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Aldrich Stevens (aldrichstevens(AT)msn.com), Jun 04 2008
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