A086802 Triangle read by rows in which row n lists (prime(n)-prime(k))/2 for 2 <= k <= n.

0, 1, 0, 2, 1, 0, 4, 3, 2, 0, 5, 4, 3, 1, 0, 7, 6, 5, 3, 2, 0, 8, 7, 6, 4, 3, 1, 0, 10, 9, 8, 6, 5, 3, 2, 0, 13, 12, 11, 9, 8, 6, 5, 3, 0, 14, 13, 12, 10, 9, 7, 6, 4, 1, 0, 17, 16, 15, 13, 12, 10, 9, 7, 4, 3, 0, 19, 18, 17, 15, 14, 12, 11, 9, 6, 5, 2, 0, 20, 19, 18, 16, 15, 13, 12, 10, 7, 6, 3, 1, 0

Offset

2,4

Links

Table of n, a(n) for n=2..92.

Formula

(3-3)/2=0; (5-3)/2=1; (5-5)/2=0; (7-3)/2=2; (7-5)/2=1; (7-7)/2=0

Example

0;
1, 0;
2, 1, 0;
4, 3, 2, 0;
5, 4, 3, 1, 0;
7, 6, 5, 3, 2, 0;
8, 7, 6, 4, 3, 1, 0;
10, 9, 8, 6, 5, 3, 2, 0

Prog

(PARI) fn2(n) = forprime(x=3, n, forprime(y=3, x, print1((x-y)/2", ")))

Crossrefs

Sequence in context: A322080 A361958 A334122 * A092488 A068527 A361989

Adjacent sequences: A086799 A086800 A086801 * A086803 A086804 A086805

Keyword

easy,tabl,nonn

Author

Cino Hilliard, Aug 05 2003

Status

approved