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

1,1

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.

Links

Table of n, a(n) for n=1..5.

Example

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.

Sequence in context: A056009 A376458 A159252 * A245329 A309171 A296791

Adjacent sequences: A357386 A357387 A357388 * A357390 A357391 A357392

Keyword

nonn,hard,more

Author

Amiram Eldar, Sep 26 2022

Status

approved