A226726 Numbers n such that the product of its decimal digits (A007954) is between n/2-1 and n/2+1.

1, 19, 27, 36, 289, 379

Offset

1,2

Comments

There are no more terms in this sequence. - Charles R Greathouse IV, Jun 15 2013

Links

Table of n, a(n) for n=1..6.

Mathematica

j[lis_] := Product[lis[[i]], {i, 1, Length[lis]}];
jj[n_] := j[RealDigits[n][[1]]]; Table[If[n/2 - 1 < j[RealDigits[n][[1]]] < n/2 + 1, n], {n, 1, 1000000}] // Union
Select[Range[400], #/2-1<Times@@IntegerDigits[#]<#/2+1&] (* Harvey P. Dale, Oct 22 2024 *)

Prog

(PARI) is(n)=my(d=digits(n)); abs(prod(i=1, #d, d[i])-n/2)<=1
select(is, vector(400, i, i))  \\ Charles R Greathouse IV, Jun 15 2013

Crossrefs

Cf. A007954

Sequence in context: A152013 A160036 A032701 * A006626 A259054 A029510

Adjacent sequences: A226723 A226724 A226725 * A226727 A226728 A226729

Keyword

nonn,fini,full,base

Author

José María Grau Ribas, Jun 15 2013

Status

approved