The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A069483

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A069483

Largest prime factor of prime(n+1)^2 - prime(n)^2.
(history; published version)

#11 by Michael De Vlieger at Sun Nov 12 11:46:04 EST 2023

STATUS

proposed

approved

#10 by Michel Marcus at Sun Nov 12 11:36:01 EST 2023

STATUS

editing

proposed

#9 by Michel Marcus at Sun Nov 12 11:35:56 EST 2023

COMMENTS

a(n) = A006530(A069482(n)).

LINKS

R. Reinhard Zumkeller, <a href="/A069483/b069483.txt">Table of n, a(n) for n = 1..1000</a>

FORMULA

a(n) = A006530(A069482(n)).

PROG

(PARI) a(n) = my(f=factor(prime(n+1)^2 - prime(n)^2)); f[#f~, 1]; \\ Michel Marcus, Nov 12 2023

CROSSREFS

Cf. A006530, A069482, A069485.

STATUS

approved

editing

#8 by Harvey P. Dale at Sun Jan 17 10:48:01 EST 2016

STATUS

editing

approved

#7 by Harvey P. Dale at Sun Jan 17 10:47:57 EST 2016

MATHEMATICA

FactorInteger[#[[2]]-#[[1]]][[-1, 1]]&/@Partition[Prime[Range[80]]^2, 2, 1] (* Harvey P. Dale, Jan 17 2016 *)

STATUS

approved

editing

#6 by Russ Cox at Fri Mar 30 18:50:20 EDT 2012

AUTHOR

_Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), _, Mar 29 2002, Aug 05 2007

Discussion

Fri Mar 30

18:50

OEIS Server: https://oeis.org/edit/global/246

#5 by N. J. A. Sloane at Thu Nov 11 07:34:06 EST 2010

LINKS

R. Zumkeller, <a href="/A069483/b069483.txt">Table of n, a(n) for n = 1..1000</a>

KEYWORD

nonn,new

nonn

#4 by N. J. A. Sloane at Fri Feb 27 03:00:00 EST 2009

LINKS

R. Zumkeller, <a href="http://www.research.att.com/~njas/sequences/b069483.txt">Table of n, a(n) for n = 1..1000</a>

KEYWORD

nonn,new

nonn

#3 by N. J. A. Sloane at Fri Jan 09 03:00:00 EST 2009

KEYWORD

nonn,new

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystemsgmail.com), Mar 29 2002, Aug 05 2007

#2 by N. J. A. Sloane at Sat Nov 10 03:00:00 EST 2007

DATA

5, 2, 3, 3, 3, 5, 3, 7, 13, 5, 17, 13, 7, 5, 5, 7, 5, 3, 23, 3, 19, 3, 43, 31, 11, 17, 7, 3, 37, 7, 43, 67, 23, 5, 5, 11, 5, 11, 17, 11, 5, 31, 3, 13, 11, 41, 31, 5, 19, 11, 59, 5, 41, 127, 13, 19, 5, 137, 31, 47, 5, 7, 103, 13, 7, 7, 167, 19, 29, 13, 89, 11, 37, 47, 127, 193, 131, 19

LINKS

R. Zumkeller, <a href="http://www.research.att.com/~njas/sequences/b069483.txt">Table of n, a(n) for n = 1..1000</a>

EXAMPLE

A069482(12) = A000040(13)^2 - A000040(12)^2 = 41^2 - 37^2 = 1681 - 1369 = 312 = 2*2*2*3*13, therefore a(12) = 13.

= 1681 - 1369 = 312 = 2*2*2*3*13, therefore a(12) = 13.

KEYWORD

nonn,new

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystems.com), Mar 29 2002, Aug 05 2007