A357389 a(n) is the start of the least run of exactly n consecutive positive integers with strictly increasing values of A071626, or -1 if no such run exists.

7, 1, 736, 26048, 991434

Offset: 1

Author

Amiram Eldar, Sep 26 2022

Keywords

• nonn
• hard
• more

Comments

a(n) is the least number k such that A071626(k) < A071626(k+1) < ... < A071626(k+n-1), but A071626(k-1) >= A071626(k) if k>1 and A071626(k+n-1) >= A071626(k+n).

a(6) > 10^7, if it exists.

Examples

			a(1) = 7 since 7 is the least positive integer that does not belong to a run of increasing values of A071626 with a length of at least 2.
a(3) = 736 since A071626(735) = A071626(736) = 26 < A071626(737) = 27 < A071626(738) = A071626(739) = 28, and 736 is the least number with this property.
		

Crossrefs

Cf. A071626, A342091, A357388, A357391.