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 A381133 #8 Mar 04 2025 23:21:10
%S A381133 0,1,1,2,1,1,1,3,2,1,1,1,1,1,1,4,1,1,1,2,1,1,1,1,2,1,3,2,1,1,1,5,1,1,
%T A381133 1,2,1,1,1,1,1,1,1,2,1,1,1,1,2,1,1,2,1,1,1,1,1,1,1,1,1,1,1,6,1,1,1,2,
%U A381133 1,1,1,3,1,1,1,2,1,1,1,1,4,1,1,1,1,1,1,3,1,1,1,2,1,1,1,1,1,1,2,2
%N A381133 If n = (p_1^e_1)*(p_2^e_2)*(p_3^e_3)*... and min(p_1^e_1,p_2^e_2,...) = p_k^e_k then a(n) = e_k, a(1) = 0.
%t A381133 Table[PrimeOmega[Min @@ (#[[1]]^#[[2]] & /@ FactorInteger[n])], {n, 100}]
%o A381133 (PARI) a(n) = if (n==1, 0, my(f=factor(n), v=vector(#f~, k, f[k,1]^f[k,2]), m=vecmin(v), i=select(x->(x==m), v, 1)); f[i[1], 2]); \\ _Michel Marcus_, Feb 19 2025
%Y A381133 Cf. A034684, A051904, A088388, A381131, A381132.
%K A381133 nonn
%O A381133 1,4
%A A381133 _Ilya Gutkovskiy_, Feb 14 2025