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%I #24 Apr 19 2023 21:52:19
%S 11,3,7,19,11,13,17,19,421,23,127,29,31,233,37,139,41,43,47,149,151,
%T 53,157,59,61,163,67,269,71,73,277,79,181,83,487,89,191,193,97,199,
%U 101,103,107,109,2111,113,1117,3119,3121,1123,127,1129,131,4133,137,139,2141,2143,5147,149,151,1153,157
%N Smallest prime ending with decimal expansion of n, for n relatively prime to 10.
%C a(n) exists by Dirichlet's theorem.
%H Robert Israel, <a href="/A338715/b338715.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Pri#piden">Index entries for primes involving decimal expansion of n</a>
%p N:= 100: # for a(1) to a(N)
%p V:= Vector(N):
%p count:= 0:
%p for n from 1 while count < N do
%p if igcd(n,10)=1 then
%p count:= count+1;
%p d:= ilog10(n)+1;
%p for x from n by 10^d do
%p if isprime(x) then V[count]:= x; break fi
%p od
%p fi
%p od:
%p convert(V,list); # _Robert Israel_, Nov 11 2020
%o (Python)
%o from sympy import isprime
%o def a(n):
%o ending = 2*n - 1 + (n+1)//4 * 2 # A045572
%o i, pow10 = ending, 10**len(str(ending))
%o while not isprime(i): i += pow10
%o return i
%o print([a(n) for n in range(1, 64)]) # _Michael S. Branicky_, Nov 03 2021
%Y Cf. A045572, A105888 (base 2 equivalent), A258190.
%Y See A245193, A337834, A338716 for other versions.
%K nonn,base,look
%O 1,1
%A _N. J. A. Sloane_, Nov 11 2020.
%E More terms from _Robert Israel_, Nov 11 2020
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