A173386 The absolute values of n-th natural noncomposite number minus n-th number k such that 6*k-+1 is a twin prime pair.

0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 4, 1, 5, 8, 5, 7, 8, 12, 9, 9, 1, 1, 2, 4, 6, 3, 2, 4, 3, 26, 24, 11, 12, 10, 31, 23, 24, 20, 19, 25, 32, 34, 34, 26, 27, 41, 43, 36, 25, 41, 41, 45, 44, 46, 47, 55, 50, 53, 54, 56, 57, 64, 55, 45, 44, 44, 56, 47, 48, 43, 48, 72, 73, 76, 75, 73, 72, 76, 70

Offset: 1

Author

Juri-Stepan Gerasimov, Feb 17 2010

Keywords

• nonn

Crossrefs

Cf. A002822, A008578.

Programs

Maple

Contribution from R. J. Mathar, Mar 09 2010: (Start)
A008578 := proc(n) if n= 1 then 1; else ithprime(n-1) ; end if; end proc:
A002822 := proc(n) if n = 1 then 1; else for a from procname(n-1)+1 do if isprime(6*a-1) and isprime(6*a+1) then return a; fi; end do ; end if; end proc:
A173386 := proc(n) abs(A008578(n)-A002822(n)) ; end proc:
seq(A173386(n),n=1..90) ; (End)

Formula

a(n) = abs(A008578(n) - A002822(n)).