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A063272 Number of times most common final digit of primes appears in first n primes.

%I A063272 #14 Jul 23 2018 02:45:10
%S A063272 1,1,1,1,1,2,2,2,3,3,3,3,3,4,4,5,5,5,5,5,6,6,7,7,7,7,8,8,8,9,9,9,9,9,
%T A063272 9,9,10,10,11,11,11,11,11,12,12,12,12,13,13,13,14,14,14,14,14,15,15,
%U A063272 15,15,15,16,17,17,17,18,18,18,18,19,19,19,19,20,20,20,21,21,21,21,21,21
%N A063272 Number of times most common final digit of primes appears in first n primes.
%H A063272 Robert Israel, <a href="/A063272/b063272.txt">Table of n, a(n) for n = 1..10000</a>
%H A063272 <a href="/index/Fi#final">Index entries for sequences related to final digits of numbers</a>
%F A063272 a(n) ~ n/phi(10) = n/4 by the Prime Number Theorem in Arithmetic Progressions. - _Charles R Greathouse IV_, Dec 29 2012
%e A063272 a(6)=2 since first six primes are 2,3,5,7,11,13, so most common final digit is 3 which has appeared twice.
%p A063272 V:= Vector(9):
%p A063272 p:= 1:
%p A063272 for n from 1 to 100 do
%p A063272   p:= nextprime(p);
%p A063272   r:= p mod 10;
%p A063272   V[r]:= V[r]+1;
%p A063272   A[n]:= max(V)
%p A063272 od:
%p A063272 seq(A[i],i=1..100); # _Robert Israel_, Jul 22 2018
%Y A063272 Cf. A000040, A007652, A063272. Slightly above floor(n/4), i.e., A002265.
%K A063272 base,nonn
%O A063272 1,6
%A A063272 _Henry Bottomley_, Jul 13 2001