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%I #31 Sep 27 2014 04:59:52
%S 0,3,7,3,7,3,3,7,3,3,7,7,3,3
%N a(n) = most common final digit for a prime < 10^n, or 0 if there is a tie.
%H <a href="/index/Fi#final">Index entries for sequences related to final digits of numbers</a>
%e For all 25 primes < 100 (10^2), we see that the last digit that appears the most is 3. Thus a(2) = 3.
%o (Python)
%o import sympy
%o from sympy import isprime
%o def prend(d,n):
%o ..lst = []
%o ..for k in range(10**n):
%o ....if isprime(k):
%o ......lst.append((k%10**d))
%o ..new = 0
%o ..newlst = []
%o ..for i in range(10**(d-1),10**d):
%o ....new = lst.count(i)
%o ....newlst.append(new)
%o ..newlst1 = newlst.copy()
%o ..a = max(newlst1)
%o ..newlst1[newlst1.index(a)] = 0
%o ..b = max(newlst1)
%o ..if a == b:
%o ....return 0
%o ..else:
%o ....return newlst.index(max(a,b)) + 10**(d-1)
%o n = 2
%o while n < 10:
%o ..print(prend(1,n),end=', ')
%o ..n += 1
%Y Cf. A007652, A095178, A244192.
%K nonn,base,hard,more
%O 1,2
%A _Derek Orr_, Jun 22 2014
%E a(9)-a(14) from _Hiroaki Yamanouchi_, Sep 27 2014
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