|
%I #28 Sep 08 2022 08:44:35
%S 2,3,4,4,6,4,6,6,8,8,6,4,8,6,10,8,12,4,6,12,4,10,12,12,6,8,8,12,8,8,8,
%T 12,8,12,12,8,4,6,16,8,18,8,14,4,12,12,6,12,12,8,12,20,6,18,8,16,16,
%U 10,4,8,6,12,12,16,4,8,6,6,12,12,8,24,10,8,12,16,16,4,8,8,24,4,20,8,16
%N Number of divisors of p+1, p prime.
%H Vincenzo Librandi, <a href="/A008329/b008329.txt">Table of n, a(n) for n = 1..2000</a>
%F a(n) = A000005(A008864(n)). - _Sean A. Irvine_, Mar 25 2018
%p for i from 1 to 500 do if isprime(i) then print(tau(i+1)); fi; od;
%p A008329 := proc(n)
%p numtheory[tau](ithprime(n)+1) ;
%p end proc: # _R. J. Mathar_, Oct 30 2015
%t DivisorSigma[0,#]&/@(Prime[Range[100]]+1) (* _Harvey P. Dale_, Apr 12 2011 *)
%o (PARI) a(n) = numdiv(prime(n)+1); \\ _Michel Marcus_, Mar 25 2018
%o (Magma) [NumberOfDivisors(NthPrime(n)+1): n in [1..100]]; // _Vincenzo Librandi_, Mar 25 2018
%Y Cf. A000005, A008864.
%K nonn
%O 1,1
%A _N. J. A. Sloane_
%E Offset corrected by _Leroy Quet_, Oct 08 2008
|
