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A204890
Ordered differences of primes.
70
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
EXAMPLE
a(1) = p(2)-p(1) = 3-2 = 1
a(2) = p(3)-p(1) = 5-2 = 3
a(3) = p(3)-p(2) = 5-3 = 2
a(4) = p(4)-p(1) = 7-2 = 5
a(5) = p(4)-p(2) = 7-3 = 4
a(6) = p(4)-p(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
Sequence in context: A143124 A205400 A205850 * A307775 A239680 A128076
KEYWORD
nonn,tabl,easy
AUTHOR
Clark Kimberling, Jan 20 2012
STATUS
approved