The On-Line Encyclopedia of Integer Sequences® (OEIS®)

Revision History for A067315 (Underlined text is an addition; strikethrough text is a ~~deletion~~.)
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A067315

Numbers k such that binomial(k, floor(k/2)) is not divisible by k.
(history; published version)

#10 by OEIS Server at Sat Aug 24 06:06:03 EDT 2024

LINKS

Amiram Eldar, <a href="/A067315/b067315_1.txt">Table of n, a(n) for n = 1..10000</a>

#9 by Michel Marcus at Sat Aug 24 06:06:03 EDT 2024

STATUS

reviewed

approved

Discussion
Sat Aug 24	06:06	OEIS Server: Installed first b-file as b067315.txt.

#8 by Joerg Arndt at Sat Aug 24 05:45:35 EDT 2024

STATUS

proposed

reviewed

#7 by Amiram Eldar at Sat Aug 24 04:20:37 EDT 2024

STATUS

editing

proposed

#6 by Amiram Eldar at Sat Aug 24 03:53:38 EDT 2024

	NAME	`CentralNumbers k binomialsuch coefficientthat Cbinomial(nk, nfloor(k/2) )) is not divisible by nk.`
	COMMENTS	`All the terms are even. - Amiram Eldar, Aug 24 2024`
	LINKS	`Amiram Eldar, <a href="/A067315/b067315_1.txt">Table of n, a(n) for n = 1..10000</a>`
	PROG	`(PARI) is(k) = binomial(k, k\2) % k > 0; \\ Amiram Eldar, Aug 24 2024`
	CROSSREFS	`Cf. A001405, A042970, A042996, (complement), A067348.`
	STATUS	`approved` `editing`

#5 by N. J. A. Sloane at Tue Oct 15 22:31:15 EDT 2013

AUTHOR

_Labos E. (labos(AT)ana.sote.hu), Elemer_, Jan 14 2002

Discussion
Tue Oct 15	22:31	OEIS Server: https://oeis.org/edit/global/2029

#4 by N. J. A. Sloane at Fri Sep 29 03:00:00 EDT 2006

NAME

Central binomial coefficient C(n,, n/2) is not divisible by n.

KEYWORD

nonn,new

nonn

#3 by N. J. A. Sloane at Fri Feb 24 03:00:00 EST 2006

MATHEMATICA

Select[ Range[ 2, , 150, , 2 ], ], Mod[ Binomial[ #, #/[ #, #/2 ], # ]> ], # ]>0& ]

KEYWORD

nonn,new

nonn

#2 by N. J. A. Sloane at Tue Jan 24 03:00:00 EST 2006

KEYWORD

nonn,new

nonn

AUTHOR

Labos E. (labos(AT)ana1ana.sote.hu), Jan 14 2002

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

	NAME	`Central binomial coefficient C(n,n/2) is not divisible by n.`
	DATA	`4, 6, 8, 10, 14, 16, 18, 20, 22, 24, 26, 28, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 86, 88, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130, 134, 136, 138, 140`
	OFFSET	`1,1`
	MATHEMATICA	`Select[ Range[ 2, 150, 2 ], Mod[ Binomial[ #, #/2 ], # ]>0& ]`
	CROSSREFS	`Cf. A001405, A042996, A067348.`
	KEYWORD	`nonn`
	AUTHOR	`Labos E. (labos(AT)ana1.sote.hu), Jan 14 2002`
	STATUS	`approved`

Last modified August 29 09:12 EDT 2024. Contains 375511 sequences. (Running on oeis4.)