A152721 - OEIS

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A152721

A prime based vector recursion: a(n)={Prime[n+1],Prime[n],Prime[n-1],-Prime[n-2],...,-1,-1}.

-1, 1, -1, 5, -1, -1, 7, -5, -1, -1, 11, -7, -5, -1, -1, 13, -11, -7, -5, -1, -1, 17, -13, -11, -7, -5, -1, -1, 19, -17, -13, -11, -7, -5, -1, -1, 23, -19, -17, -13, -11, -7, -5, -1, -1, 29, -23, -19, -17, -13, -11, -7, -5, -1, -1, 31, -29, -23, -19, -17, -13, -11, -7, -5

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OFFSET

0,4

COMMENTS

Row sums are:

{-1, 0, 3, 0, -3, -12, -21, -36, -51, -68, -95,...}

LINKS

Table of n, a(n) for n=0..63.

FORMULA

a(n)={Prime[n+1],Prime[n],Prime[n-1],-Prime[n-2],...,-1,-1}.

EXAMPLE

{-1},

{1, -1},

{5, -1, -1},

{7, -5, -1, -1},

{11, -7, -5, -1, -1},

{13, -11, -7, -5, -1, -1},

{17, -13, -11, -7, -5, -1, -1},

{19, -17, -13, -11, -7, -5, -1, -1},

{23, -19, -17, -13, -11, -7, -5, -1, -1},

{29, -23, -19, -17, -13, -11, -7, -5, -1, -1},

{31, -29, -23, -19, -17, -13, -11, -7, -5, -1, -1}

MATHEMATICA

b[0] = {-1}; b[1] = {1, -1};

b[n_] := b[n] = Join[{Prime[n + 1 ]}, {-b[n - 1][[1]]}, Table[b[n - 1][[i]], {i, 2, Length[b[n - 1]]}]];

Table[b[n], {n, 0, 10}]; Flatten[%]

CROSSREFS

A152568, A027293

Sequence in context: A324385 A111720 A029646 * A132737 A137754 A131404

Adjacent sequences: A152718 A152719 A152720 * A152722 A152723 A152724

KEYWORD

sign

AUTHOR

Roger L. Bagula, Dec 11 2008

STATUS

approved