A336721 Values k where A336719(k) increases.

2, 3, 5, 7, 13, 17, 19, 31, 49, 61, 83, 89, 107, 127, 167, 179, 197, 233, 241, 269, 281, 347, 373, 421, 443, 457, 487, 521, 607, 697, 769, 829, 881, 1049, 1063

Offset: 1

Author

Jeppe Stig Nielsen, Aug 01 2020

Keywords

• nonn
• hard
• more

Comments

Also, values k (record positions) where A005420(k) reaches a new maximum. For the maximum itself, see A336720.

A000043 is a subsequence.

Crossrefs

Cf. A000043, A005420, A336719, A336720.

Programs

PARI

re=0;for(k=2,+oo,p=vecmax(factor(2^k-1)[,1]);if(p>re,re=p;print1(k,", ")))