a(n) is the smallest number k such that the number of divisors of the n numbers from k through k+n-1 are nonincreasing.

5

`%I #16 Mar 27 2019 18:40:39
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`%S 1,2,20,20,714,714,25550,90180,142803,809300,27195648,27195648,
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`%T 6973441007,37962822225,37962822225,114296059262,265228019405583,
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`%U 394047434860662,2493689139940250
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`%N a(n) is the smallest number k such that the number of divisors of the n numbers from k through k+n-1 are nonincreasing.
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`%C tau(k) >= tau(k+1) >= ... >= tau(k+n-1).
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`%C Next term is > 2000000. - _David Wasserman_, May 06 2005
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`%C a(17) > 10^12. [_Donovan Johnson_, Oct 13 2009]
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`%C a(20) > 2.64x10^15. - _Jud McCranie_, Mar 27 2019
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`%e a(3)=a(4) = 20 as tau(20) > tau(21) = tau(22) > tau(23).
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`%Y Cf. A075028, A075029, A075046.
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`%K nonn,more
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`%O 1,2
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`%A _Amarnath Murthy_, Sep 02 2002
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`%E More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 19 2003
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`%E a(11)-a(16) from _Donovan Johnson_, Oct 13 2009
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`%E a(17)-a(19) from _Jud McCranie_, Mar 27 2019
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