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 A226726 #14 Oct 22 2024 18:10:15
%S A226726 1,19,27,36,289,379
%N A226726 Numbers n such that the product of its decimal digits (A007954) is between n/2-1 and n/2+1.
%C A226726 There are no more terms in this sequence. - _Charles R Greathouse IV_, Jun 15 2013
%t A226726 j[lis_] := Product[lis[[i]], {i, 1, Length[lis]}];
%t A226726 jj[n_] := j[RealDigits[n][[1]]]; Table[If[n/2 - 1 < j[RealDigits[n][[1]]] < n/2 + 1, n], {n, 1, 1000000}] // Union
%t A226726 Select[Range[400],#/2-1<Times@@IntegerDigits[#]<#/2+1&] (* _Harvey P. Dale_, Oct 22 2024 *)
%o A226726 (PARI) is(n)=my(d=digits(n));abs(prod(i=1,#d,d[i])-n/2)<=1
%o A226726 select(is,vector(400,i,i)) \\ _Charles R Greathouse IV_, Jun 15 2013
%Y A226726 Cf. A007954
%K A226726 nonn,fini,full,base
%O A226726 1,2
%A A226726 _José María Grau Ribas_, Jun 15 2013