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.

2, 20164, 155236, 293761, 293762, 643204, 1435204, 1444802, 5216653, 6120676, 8421601, 8421602, 14047501, 15194404, 15984004, 17606413, 19114383, 22829284, 25786083, 25989602, 35259843, 35259844, 36264484, 41499364, 42876301, 44382241, 50523662, 50523663

Offset: 1

Author

Michel Lagneau, Feb 11 2010

Keywords

• nonn

Examples

			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.
		

Links

• Giovanni Resta, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A000005, A006558.

Programs

Maple

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;

Mathematica

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

Extensions

a(13)-a(28) from Giovanni Resta, Jun 12 2016