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%I #16 Dec 17 2017 11:57:40
%S 0,0,0,1,0,1,0,1,1,0,1,1,0,1,1,1,0,1,1,0,1,1,1,3,1,0,1,0,1,5,1,1,0,3,
%T 0,1,1,1,1,1,0,3,0,1,0,3,3,1,0,1,1,0,3,1,1,1,0,1,1,0,3,5,1,0,1,5,1,3,
%U 0,1,1,3,1,1,1,1,3,1,3,3,0,3,0,1,1,1,3,1,0,1,3,3,1,3,1,1,3,0,5,1
%N Number of integers between p(n) and p(n+1) which are coprime to (p(n+1)-p(n)), where p(n) is the n-th prime.
%F a(n) = phi(p(n+1)-p(n)) - 1, where phi(n) = A000010(n).
%e Between the primes p(24) = 89 and p(25) = 97 are 3 integers (91, 93 and 95) which are coprime to (p(25)-p(24)) = 8, so a(24) = 3.
%t Table[EulerPhi[Prime[n + 1] - Prime[n]] - 1, {n, 1, 70}] (* _Stefan Steinerberger_, Mar 30 2006 *)
%o (MuPAD) for n from 2 to 100 do a := ithprime(n); b := nextprime(a+1); su := 0; for k from a+1 to b-1 do if gcd(k,(b-a)) = 1 then su := su+1; end_if; end_for; print(su); end_for; // _Stefan Steinerberger_
%K nonn
%O 1,24
%A _Leroy Quet_, Nov 17 2005
%E More terms from _Stefan Steinerberger_, Nov 19 2005
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