A037049 - OEIS

A037049

Smallest number with two distinct prime factors both of length n.

6, 143, 10403, 1022117, 100160063, 10002200057, 1000036000099, 100000980001501, 10000004400000259, 1000000016000000063, 100000000520000000627, 10000000002200000000057, 1000000000100000000002379, 100000000000880000000001887, 10000000000009800000000002077

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

a(3)=10403 -> equals 101 * 103.

MATHEMATICA

tdpf[n_]:=Module[{f1=NextPrime[Floor[Sqrt[10^n]]]}, {IntegerLength[f1], f1* NextPrime[f1]}]; Join[{6}, Table[SelectFirst[Array[tdpf, 50], #[[1]]==n&], {n, 2, 20}][[All, 2]]] (* Harvey P. Dale, Apr 06 2018 *)

CROSSREFS

Sequence in context: A349069 A111839 A349076 * A196811 A200457 A128785

Adjacent sequences: A037046 A037047 A037048 * A037050 A037051 A037052

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jan 04 1999

EXTENSIONS

Corrected and extended by Harvey P. Dale, Apr 06 2018

STATUS

approved