login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A131551 Least power of 3 having exactly n consecutive 2's in its decimal representation. 9
3, 19, 148, 253, 330, 2380, 2124, 30598, 22791, 238582, 107187, 1521134, 10363119, 9995030, 68353787 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

a(3)=148 because 3^148(i.e. 41109831670569663658300086939077404909608122265524774868353822811305361) is the smallest power of 3 to contain a run of 3 consecutive twos in its decimal form.

MATHEMATICA

a = ""; Do[ a = StringJoin[a, "2"]; b = StringJoin[a, "2"]; k = 1; While[ StringPosition[ ToString[3^k], a] == {} || StringPosition[ ToString[3^k], b] != {}, k++ ]; Print[k], {n, 1, 10} ]

CROSSREFS

Cf. A195269, A131552, A131550, A131549, A131548, A131547, A131546, A131545, A131544.

Sequence in context: A080833 A073516 A005258 * A074546 A054316 A006289

Adjacent sequences:  A131548 A131549 A131550 * A131552 A131553 A131554

KEYWORD

more,nonn,base

AUTHOR

Shyam Sunder Gupta, Aug 26 2007

EXTENSIONS

a(11)-a(14) from Lars Blomberg, Feb 02 2013

a(15) from Bert Dobbelaere, Mar 04 2019

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 2 13:40 EDT 2020. Contains 335401 sequences. (Running on oeis4.)