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A075029
Smallest initial number k of n consecutive numbers satisfying numdiv(k) > numdiv(k+1) > ... > numdiv(k+n-1).
8
1, 4, 45, 80, 28974, 28974, 8489103, 80314575, 5196065775, 77506573550, 166622964149389, 489289301397948
OFFSET
1,2
COMMENTS
a(11) > 10^12. - Donovan Johnson, Oct 13 2009
a(11) > 10^13. - Giovanni Resta, Jul 25 2013
a(13) > 2.64*10^15. - Jud McCranie, Mar 27 2019
REFERENCES
J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 45, p. 17, Ellipses, Paris 2008.
EXAMPLE
a(4) = 80, as tau(80) = 10 > tau(81) = 5 > tau(82) = 4 > tau(83) = 2.
PROG
(PARI) n=2; for(k=1, 100, while(1, m=n; s=1; while(numdiv(m)<numdiv(m-1), s=s+1; m=m+1); if(s>=k, print1(n-1, ", "); break); n=n+1))
CROSSREFS
Sequence in context: A024254 A167781 A173327 * A369228 A070225 A132998
KEYWORD
nonn,more
AUTHOR
Amarnath Murthy, Sep 02 2002
EXTENSIONS
Edited by Ralf Stephan, Mar 21 2003
Definition corrected by Leroy Quet, Feb 23 2008
2 more terms from Lekraj Beedassy, Jul 13 2008
a(9)-a(10) from Donovan Johnson, Oct 13 2009
a(11)-a(12) from Jud McCranie, Mar 27 2019
STATUS
approved