Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
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!)

Revision History for A134361

(Underlined text is an addition; strikethrough text is a deletion.)

Showing all changes.
A134361 a(n) = smallest integer >= n which has only prime factors 2 and 3.
(history; published version)
#10 by Charles R Greathouse IV at Fri Jul 09 12:10:34 EDT 2021
STATUS

editing

approved

#9 by Charles R Greathouse IV at Fri Jul 09 12:10:23 EDT 2021
COMMENTS

Can be used, for example, to derive A084788 and A084790 from A084789. - Charles R Greathouse IV, Jul 09 2021

PROG

(PARI) a(n)=my(v=List()); for(i=0, logint(n, 3)+1, my(t=3^i); t<<=if(t>n, 0, exponent(n\t)+1); listput(v, t)); Set(v)[1] \\ Charles R Greathouse IV, Jul 09 2021

KEYWORD

nonn,easy

STATUS

approved

editing

#8 by Charles R Greathouse IV at Thu Nov 21 12:49:08 EST 2013
MATHEMATICA

With[{pf23=Union[Flatten[Table[Times@@@Tuples[{2, 3}, n], {n, 0, 6}]]]}, Flatten[Table[Select[pf23, #>=n&, 1], {n, 80}]]] (* From }]]] (* _Harvey P. Dale, _, Mar 07 2012 *)

Discussion
Thu Nov 21 12:49
OEIS Server: https://oeis.org/edit/global/2062
#7 by Russ Cox at Fri Mar 30 16:50:46 EDT 2012
AUTHOR

_N. J. A. Sloane (njas(AT)research.att.com), _, Aug 23 2009; corrected Mar 07 2012

Discussion
Fri Mar 30 16:50
OEIS Server: https://oeis.org/edit/global/110
#6 by Harvey P. Dale at Wed Mar 07 14:29:27 EST 2012
STATUS

editing

approved

#5 by Harvey P. Dale at Wed Mar 07 14:29:23 EST 2012
MATHEMATICA

With[{pf23=Union[Flatten[Table[Times@@@Tuples[{2, 3}, n], {n, 0, 6}]]]}, Flatten[Table[Select[pf23, #>=n&, 1], {n, 80}]]] (* From Harvey P. Dale, Mar 07 2012 *)

STATUS

approved

editing

#4 by N. J. A. Sloane at Wed Mar 07 12:50:05 EST 2012
STATUS

editing

approved

#3 by N. J. A. Sloane at Wed Mar 07 12:50:00 EST 2012
DATA

1, 32, 3, 54, 56, 96, 98, 98, 9, 1512, 1512, 1512, 1516, 1516, 1516, 2516, 2518, 2518, 2524, 2524, 2524, 2524, 2524, 2524, 2527, 27, 27, 32, 32, 32, 4532, 4532, 4536, 4536, 4536, 4536, 4548, 4548, 4548, 4548, 4548, 4548, 4548, 4548, 4548, 4548, 4548, 4548, 7554, 7554, 7554, 7554, 7554, 7554, 7564, 7564, 7564, 7564, 7564, 7564, 7564, 7564, 7564, 7564, 7572, 7572, 7572, 7572, 7572, 7572, 7572, 7572

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Aug 23 2009; corrected Mar 07 2012

STATUS

approved

editing

#2 by N. J. A. Sloane at Tue Jun 01 03:00:00 EDT 2010
NAME

Cardinality of the largesta(n) = smallest criticalinteger >= n setwhich inhas anyonly Latinprime squarefactors of2 orderand n3.

DATA

0, 1, 3, 3, 5, 5, 9, 9, 9, 9, 15, 15, 15, 15, 15, 15, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 27, 27, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 75, 775, 1175, 1875

OFFSET

1,32

COMMENTS

A critical set in an n x n array is a set C of given entries,

such that there exists a unique extension of C to an n x n Latin

square and no proper subset of C has this property.

LINKS

H. Hatami and E. S. Mahmoodian, <a href="http://arXiv.org/abs/math/0701014">A lower bound for the size of the largest critical sets in Latin squares</a>

PROG

(R) f <- function(n) nextn(n, factors = c(2, 3))

a <- matrix(1:256, ncol=1)

apply(a, 1, f)

CROSSREFS

Cf. A130916, A134361, A151969.

KEYWORD

nonn,hard,new

nonn

AUTHOR

Ralf Stephan, Jan 16 2008

N. J. A. Sloane (njas(AT)research.att.com), Aug 23 2009

#1 by N. J. A. Sloane at Sun Jun 29 03:00:00 EDT 2008
NAME

Cardinality of the largest critical set in any Latin square of order n.

DATA

0, 1, 3, 7, 11, 18

OFFSET

1,3

COMMENTS

A critical set in an n x n array is a set C of given entries,

such that there exists a unique extension of C to an n x n Latin

square and no proper subset of C has this property.

LINKS

H. Hatami and E. S. Mahmoodian, <a href="http://arXiv.org/abs/math/0701014">A lower bound for the size of the largest critical sets in Latin squares</a>

KEYWORD

nonn,hard

AUTHOR

Ralf Stephan, Jan 16 2008

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 August 18 23:05 EDT 2024. Contains 375284 sequences. (Running on oeis4.)