This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A067367 #10 Mar 08 2018 14:00:11 %S A067367 5,23,29,43,89,107,139,193,199,211,229,239,313,347,419,457,587,641, %T A067367 661,673,701,739,863,877,1091,1097,1103,1217,1259,1283,1361,1381,1447, %U A067367 1493,1549,1607,1609,1663,1693,1741,1861,1973,1987,2083,2251,2351,2399,2423 %N A067367 Primes p such that the number of digits in p! is also prime. %H A067367 Vincenzo Librandi, <a href="/A067367/b067367.txt">Table of n, a(n) for n = 1..450</a> %e A067367 a(1)=5 because 5!=120 has 3 (prime) digits. %t A067367 Select[ Select[ Range[2500], PrimeQ[ Floor[ Log[10, #! ] + 1]] & ], PrimeQ[ # ] & ] %t A067367 Select[Prime[Range[400]],PrimeQ[IntegerLength[#!]]&] (* _Harvey P. Dale_, Mar 08 2018 *) %Y A067367 Cf. A035065. %K A067367 nonn,base %O A067367 1,1 %A A067367 Sudipta Das (juitech(AT)vsnl.net), Feb 23 2002 %E A067367 Edited and extended by _Robert G. Wilson v_, Feb 28 2002