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A163504
a(n) = abs(n-th prime minus n-th odd nonprime).
1
1, 6, 10, 14, 14, 14, 16, 16, 16, 16, 18, 14, 14, 14, 16, 12, 10, 14, 10, 10, 12, 8, 8, 4, 2, 2, 2, 4, 6, 4, 8, 10, 14, 14, 20, 18, 22, 22, 24, 28, 32, 28, 36, 34, 36, 34, 42, 52, 52, 52, 50, 54, 54, 62, 62, 62, 66, 66, 70, 72, 70, 78, 90, 92, 92, 92, 100, 102, 110, 106, 108, 112
OFFSET
1,2
LINKS
FORMULA
a(n) = abs(A000040(n)-A014076(n)).
EXAMPLE
a(1)=abs(2-1)=1; a(2)=abs(3-9)=6.
MAPLE
A014076 := proc(n) option remember; local a; if n = 1 then 1; else for a from procname(n-1)+2 by 2 do if not isprime(a) then return a; end if; end do: end if; end proc: A163504 := proc(n) abs(ithprime(n)-A014076(n)) ; end: seq(A163504(n), n=1..80) ; # R. J. Mathar, Oct 10 2009
MATHEMATICA
A014076 := Select[Range[1, 10000, 2], PrimeOmega[#] != 1 &]; Table[Abs[Prime[n] - A014076[[n]]], {n, 1, 50}] (* G. C. Greubel, Jul 27 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
An 8 inserted by R. J. Mathar, Oct 10 2009
STATUS
approved