The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A067127 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A067127

Composite numbers for which phi(n) >= phi(k) for all composite k from 1 to n-1.
(history; published version)

#8 by OEIS Server at Tue Dec 10 20:01:51 EST 2024

LINKS

Andrew Howroyd, <a href="/A067127/b067127_1.txt">Table of n, a(n) for n = 1..10000</a>

#7 by Alois P. Heinz at Tue Dec 10 20:01:51 EST 2024

STATUS

proposed

approved

Discussion

Tue Dec 10

20:01

OEIS Server: Installed first b-file as b067127.txt.

#6 by Andrew Howroyd at Tue Dec 10 19:37:51 EST 2024

STATUS

editing

proposed

#5 by Andrew Howroyd at Tue Dec 10 19:37:38 EST 2024

CROSSREFS

Cf. A067126, A131195.

#4 by Andrew Howroyd at Tue Dec 10 19:35:57 EST 2024

LINKS

Andrew Howroyd, <a href="/A067127/b067127_1.txt">Table of n, a(n) for n = 1..10000</a>

PROG

(PARI) lista(n)={my(L=List(), m=0); for(k=2, oo, if(!isprime(k), my(t=eulerphi(k)); if(t>=m, listput(L, k); m=t; if(#L>=n, return(Vec(L))))))} \\ Andrew Howroyd, Dec 10 2024

STATUS

approved

editing

#3 by N. J. A. Sloane at Thu Dec 05 19:55:08 EST 2013

AUTHOR

_Amarnath Murthy (amarnath_murthy(AT)yahoo.com), _, Jan 09 2002

Discussion

Thu Dec 05

19:55

OEIS Server: https://oeis.org/edit/global/2075

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

NAME

Composite Numbers numbers for which phi(n) >= phi(k) for all composite k from 1 to n-1.

OFFSET

0,1,1

KEYWORD

easy,nonn,new

#1 by N. J. A. Sloane at Fri May 16 03:00:00 EDT 2003

NAME

Composite Numbers for which phi(n) >= phi(k) for all composite k from 1 to n-1.

DATA

4, 6, 8, 9, 14, 15, 16, 20, 21, 25, 33, 35, 39, 45, 49, 65, 77, 85, 91, 95, 111, 115, 119, 121, 143, 155, 161, 169, 187, 203, 209, 217, 221, 247, 253, 287, 289, 319, 323, 341, 361, 391, 403, 407, 427, 437, 451, 473, 481, 493, 517, 527, 529, 583, 589, 611, 629

OFFSET

0,1

EXAMPLE

33 is a member as phi(33)=20 which is >= the maximum phi value for composite numbers less than 33, namely phi(25)=20.

CROSSREFS

Cf. A067126.

KEYWORD

easy,nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jan 09 2002

STATUS

approved