A094382 Number of quadruples (p, p+d, p+2*d, p+3*d) of primes with d>0 and p+3*d<=n.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 11, 11, 11, 11

Offset: 1

Author

Reinhard Zumkeller, Apr 28 2004

Keywords

• nonn

Examples

			a(50)=4: 5=prime(3) -> 5+6=11=prime(5) -> 11+6=17=prime(7) ->
17+6=23=prime(9), 5=prime(3) -> 5+12=17=prime(7) -> 17+12=29=prime(10) ->
29+12=41=prime(13), 7=prime(4) -> 7+12=19=prime(8) -> 19+12=31=prime(11) ->
31+12=43=prime(14) and 11=prime(5) -> 11+6=17=prime(7) -> 17+6=23=prime(9)
-> 23+6=29=prime(10),
		

Links

• Index entries for sequences related to primes in arithmetic progressions

Crossrefs

Cf. A093354, A094383.