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 A137807 #9 Jan 20 2022 13:47:06 %S A137807 4,9,5,9,1,9,9,1,9,1,1,9,1,9,9,9,1,1,9,1,9,1,9,1,9,1,9,9,1,9,9,1,9,1, %T A137807 1,1,9,9,9,9,1,1,1,9,9,1,1,9,9,1,9,1,1,1,9,9,1,1,9,1,9,9,9,1,9,9,1,9, %U A137807 9,1,9,1,9,9,1,9,1,9,1,1,1,1,1,9,1,9,1,9,1,9,9,1,9,1,1,9,1,1,9,1,9,9,9,1,1 %N A137807 Final digit of prime(n)^2. %C A137807 Euler and Sadek ask whether the sequence, interpreted as the decimal expansion N = 0.49591..., is rational or irrational. - _Charles R Greathouse IV_, Apr 19 2010 %D A137807 R. Euler and J. Sadek, A number that gives the unit digit of n^n. Journal of Recreational Mathematics, 29:3 (1998), pp. 203-204. [From _Charles R Greathouse IV_, Apr 19 2010] %F A137807 a(n) = A010879(A001248(n)). - _R. J. Mathar_, May 03 2008 %p A137807 A001248 := proc(n) ithprime(n)^2 ; end: A010879 := proc(n) n mod 10 ; end: A137807 := proc(n) A010879(A001248(n)) ; end: seq(A137807(n),n=1..140) ; # _R. J. Mathar_, May 03 2008 %t A137807 Mod[Prime[Range[110]]^2,10] (* _Harvey P. Dale_, Jan 20 2022 *) %K A137807 nonn,base %O A137807 1,1 %A A137807 _Paul Curtz_, Apr 29 2008 %E A137807 More terms from _R. J. Mathar_, May 03 2008