

A086802


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


1



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
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OFFSET

2,4


LINKS

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


FORMULA

(33)/2=0; (53)/2=1; (55)/2=0; (73)/2=2; (75)/2=1; (77)/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((xy)/2", ")))


CROSSREFS

Sequence in context: A201701 A131667 A322080 * A092488 A068527 A218599
Adjacent sequences: A086799 A086800 A086801 * A086803 A086804 A086805


KEYWORD

easy,tabl,nonn


AUTHOR

Cino Hilliard, Aug 05 2003


STATUS

approved



