A204890 Ordered differences of primes.

1, 3, 2, 5, 4, 2, 9, 8, 6, 4, 11, 10, 8, 6, 2, 15, 14, 12, 10, 6, 4, 17, 16, 14, 12, 8, 6, 2, 21, 20, 18, 16, 12, 10, 6, 4, 27, 26, 24, 22, 18, 16, 12, 10, 6, 29, 28, 26, 24, 20, 18, 14, 12, 8, 2, 35, 34, 32, 30, 26, 24, 20, 18, 14, 8, 6, 39, 38, 36, 34, 30, 28, 24, 22

Offset

1,2

Comments

For a guide to related sequences, see A204892.

A086800, zeros omitted. - R. J. Mathar, Sep 15 2012

Links

Table of n, a(n) for n=1..74.

Example

a(1) = prime(2)-prime(1) = 3-2 = 1
a(2) = prime(3)-prime(1) = 5-2 = 3
a(3) = prime(3)-prime(2) = 5-3 = 2
a(4) = prime(4)-prime(1) = 7-2 = 5
a(5) = prime(4)-prime(2) = 7-3 = 4
a(6) = prime(4)-prime(3) = 7-5 = 2
From Michel Marcus, May 12 2016: (Start)
As a triangle, first rows are:
  1;
  3, 2;
  5, 4, 2;
  9, 8, 6, 4;
  11, 10, 8, 6, 2; (End)

Mathematica

(See the program at A204892.)
With[{prs=Prime[Range[20]]}, Flatten[Table[prs[[n]]-Take[prs, n-1], {n, 2, Length[prs]}]]] (* Harvey P. Dale, Dec 01 2013 *)

Prog

(PARI) tabl(nn) = {for (n=2, nn, for (m=1, n-1, print1(prime(n) - prime(m), ", "); ); print(); ); } \\ Michel Marcus, May 12 2016

Crossrefs

Cf. A204892, A090321, A086800.

Sequence in context: A143124 A205400 A205850 * A307775 A239680 A128076

Adjacent sequences: A204887 A204888 A204889 * A204891 A204892 A204893

Keyword

nonn,tabl,easy

Author

Clark Kimberling, Jan 20 2012

Status

approved