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A173156 Numbers n such that max(tau(n),tau(n+1),tau(n+2),tau(n+3))- min(tau(n),tau(n+1),tau(n+2),tau(n+3)) = 1. 1

%I #15 Jan 23 2023 15:34:00

%S 2,20164,155236,293761,293762,643204,1435204,1444802,5216653,6120676,

%T 8421601,8421602,14047501,15194404,15984004,17606413,19114383,

%U 22829284,25786083,25989602,35259843,35259844,36264484,41499364,42876301,44382241,50523662,50523663

%N Numbers n such that max(tau(n),tau(n+1),tau(n+2),tau(n+3))- min(tau(n),tau(n+1),tau(n+2),tau(n+3)) = 1.

%H Giovanni Resta, <a href="/A173156/b173156.txt">Table of n, a(n) for n = 1..1000</a>

%e For n = 20164, max(tau(20164),tau(20165),tau(20166),tau(20167)) - min(tau(20164),tau(20165),tau(20166),tau(20167)) = max(9,8,8,8) - min(9,8,8,8) = 1.

%p with(numtheory):for n from 200000 to 1500000 do;if max(tau(n),tau(n+1),tau(n+2),tau(n+3))- min(tau(n),tau(n+1),tau(n+2),tau(n+3))= 1 then print(n); else fi ; od;

%t Position[Partition[DivisorSigma[0,Range[5053*10^4]],4,1],_?(Max[#]-Min[#] == 1&)]// Flatten (* _Harvey P. Dale_, Jan 23 2023 *)

%Y Cf. A000005, A006558.

%K nonn

%O 1,1

%A _Michel Lagneau_, Feb 11 2010

%E a(13)-a(28) from _Giovanni Resta_, Jun 12 2016

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Last modified March 19 04:58 EDT 2024. Contains 370952 sequences. (Running on oeis4.)