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%I #26 Mar 19 2024 22:34:40
%S 2,241,2467,24683,2468101,246810121,24681012149,24681012141601,
%T 2468101214161811,246810121416182039,24681012141618202211,
%U 2468101214161820222441,246810121416182022242641,246810121416182022242628043,24681012141618202224262830073
%N Smallest prime with concatenation of first n even numbers as leading digits.
%C a(350) has 1001 digits. - _Michael S. Branicky_, Mar 19 2024
%H Michael S. Branicky, <a href="/A068838/b068838.txt">Table of n, a(n) for n = 1..349</a> (terms 1..300 from _Harvey P. Dale_ with corrections to terms 1..175 by _Sean A. Irvine_ and corrections in 176..300 by _Michael S. Branicky_)
%o (Python)
%o from sympy import isprime
%o from itertools import count
%o def a(n):
%o if n == 1: return 2
%o prefix = int("".join(map(str, (2*i for i in range(1, n+1)))))
%o for extra in count(1):
%o prefix *= 10
%o for i in range(10**extra):
%o t = prefix + i
%o if isprime(t): return t
%o print([a(n) for n in range(1, 16)]) # _Michael S. Branicky_, Mar 19 2024
%K nonn,base
%O 1,1
%A _Amarnath Murthy_, Mar 09 2002
%E More terms from _Benoit Cloitre_, Mar 10 2002
%E Corrected by _T. D. Noe_, Nov 15 2006
%E Corrected and extended by _Jayanta Basu_, Aug 09 2013
%E Data corrected by _Sean A. Irvine_, Mar 19 2024
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