login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A273382 Numbers x = concat(a,b) such that a^b begins with the digits of x. 3
7525, 7533, 251196, 264770, 304732, 1768696, 2605292, 2653884, 32554685, 46415894 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..10.

EXAMPLE

7525 is a member because 75^25 is equal to 752543...6875, i.e., its first digits are 7525.

MATHEMATICA

beg[x_, y_, n_] := x > 0 && Log10[x]*y >= Log10[n] && Block[{u = FractionalPart@ Log10[n+1]}, FractionalPart@ Log10[n] <= FractionalPart[ Log10[x]*y] < If[u == 0, 1, u]]; ok[n_] := Block[{p=1}, While[(p *= 10) < n && ! beg[Floor[n/p], Mod[n, p], n]]; p < n]; Select[Range[10^6], ok]

CROSSREFS

Cf. A266817, A266818, A273383.

Sequence in context: A258604 A093225 A090742 * A186938 A185749 A077096

Adjacent sequences:  A273379 A273380 A273381 * A273383 A273384 A273385

KEYWORD

nonn,base,more

AUTHOR

Giovanni Resta, Jun 06 2016

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 25 18:25 EDT 2022. Contains 354071 sequences. (Running on oeis4.)