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%I A103835 #8 May 25 2024 20:46:04
%S A103835 3,11,13,19,23,31,43,53,67,97,113,149,151,173,193,223,239,251,373,389,
%T A103835 397,409,431,439,457,479,487,499,569,577,601,647,739,757,797,809,811,
%U A103835 821,827,829,863,929,991,1109,1181,1297,1301,1303,1327,1367,1409,1429
%N A103835 Smallest prime p, larger than previous term, such that concatenation of n and p is a prime.
%C A103835 Cf. A096915.
%e A103835 a(10)=97 because 1097 is prime, while 1071,1073,1079,1083,1089 are all composite.
%o A103835 (Python)
%o A103835 from sympy import isprime, nextprime
%o A103835 def ispal(n): s = str(n); return s == s[::-1]
%o A103835 def aupto(lim):
%o A103835   n, p, alst = 1, 2, []
%o A103835   while p <= lim:
%o A103835     if isprime(int(str(n)+str(p))): n, alst = n + 1, alst + [p]
%o A103835     p = nextprime(p)
%o A103835   return alst
%o A103835 print(aupto(1429)) # _Michael S. Branicky_, Mar 11 2021
%Y A103835 Cf. A096915, A103836.
%K A103835 nonn,base
%O A103835 1,1
%A A103835 _Zak Seidov_, Mar 30 2005

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