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%I #8 Jul 11 2014 09:10:41
%S 1,6,40,268,2103,17623,146590,1274284,11272025,101053126,915755611,
%T 8372478663,77114448042,714719245204
%N a(n) = the frequency of the most common final digit of a prime with n digits.
%C For the most common final digit, see A244189.
%e Of the 3-digit primes, there are 35 that end in 1, 35 that end in 3, 40 that end in 7, and 33 that end in 9. Thus since 7 has the most, a(3) = 40.
%o (Python)
%o import sympy
%o from sympy import isprime
%o def end1(d,n):
%o ..lst = []
%o ..for k in range(10**(d-1),10**d):
%o ....num = ''
%o ....count = 0
%o ....for i in range(10**(n-d-1),10**(n-d)):
%o ......if isprime(int(str(i)+str(k))):
%o ........count += 1
%o ....lst.append(count)
%o ..return max(lst)
%o n = 2
%o while n < 10:
%o ..print(end1(1,n),end=', ')
%o ..n += 1
%Y Cf. A244189.
%K nonn,base,more,hard
%O 1,2
%A _Derek Orr_, Jun 24 2014
%E a(8)-a(14) from _Hiroaki Yamanouchi_, Jul 10 2014
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