A306879 Smallest number m such that m, m+1, and m+2 all have exactly 2p divisors, where p = prime(n).

33, 242, 7939375, 76571890623, 104228508212890623, 1489106237081787109375, 273062471666259918212890623, 804505911103256259918212890623, 490685203356467392256259918212890623, 6794675247932944436619977392256259918212890623, 329757106427071213106619977392256259918212890623

Offset

1,1

Comments

a(4) was incorrect in "Some new results on consecutive equidivisible integers".

Links

Chai Wah Wu, Table of n, a(n) for n = 1..50

Vasilii A. Dziubenko, Vladimir A. Letsko, Consecutive positive integers with the same number of divisors, arXiv:1811.05127 [math.NT], 2018.

Vladimir A. Letsko, Some new results on consecutive equidivisible integers, arXiv:1510.07081 [math.NT], 2015.

Example

33, 34, 35 all have exactly 2*prime(1) = 4 divisors, and 33 is the smallest number with this property, so a(1) = 33.

Crossrefs

Cf. A274639.

A subsequence of A075040.

Sequence in context: A075040 A353938 A274639 * A178448 A351268 A088703

Adjacent sequences: A306876 A306877 A306878 * A306880 A306881 A306882

Keyword

nonn

Author

Chai Wah Wu, Mar 14 2019

Status

approved