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 A147803 #12 Aug 12 2020 01:28:47
%S A147803 1,1,4,49,128,9,36864,19332,4508,121,2
%N A147803 Least m coprime to 5 minimizing A007947(m*(5^n-m)).
%C A147803 The minima are given in A147800.
%C A147803 This is related to the abc conjecture: Since m is coprime to 5, it is also coprime to 5^n and thus to 5^n-m. Thus the squarefree kernel A007947(m*(5^n-m)*5^n) = 5*A007947(m*(5^n-m)).
%o A147803 (PARI) A147803(n,p=5) = {my(b, m=n=p^n); for(a=1, n\2, a%p || next; A007947(n-a)*A007947(a)<m || next; m=A007947((n-a)*b=a)); b; }
%Y A147803 Cf. A007947, A147298 (general case), A147800 (value of minima), A143700 (analog for 2^n), A147802 (analog for 3^n), A147300 (analog for any number).
%K A147803 nonn,more
%O A147803 1,3
%A A147803 _M. F. Hasler_, Nov 13 2008