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 A169962 #4 Mar 30 2012 16:51:46 %S A169962 0,0,28,44,168,612,2520,10356,44712,195120,868224,3905388,17756424, %T A169962 81376140,375603480,1743843924,8138028696,38146891320,179515196280, %U A169962 847710124128,4015470916296,19073484584388,90826125756552,433488317523588,2073205037124648 %N A169962 Number of n-digit primes in carryless arithmetic mod 10. %H A169962 <a href="/index/Ca#CARRYLESS">Index entries for sequences related to carryless arithmetic</a> %F A169962 For formula see Maple code. %p A169962 with(numtheory); f:=proc(n) local t1,d; if n <= 1 then RETURN(0); fi; t1:=0; for d from 1 to n-1 do if n-1 mod d = 0 then t1:=t1+(4/(n-1))*mobius((n-1)/d)*(2^d+5^d); fi; od: t1; end; %Y A169962 See A169887 for the actual primes. %K A169962 nonn,base %O A169962 0,3 %A A169962 _N. J. A. Sloane_, Aug 07 2010