A370999 Least composite number k such that the number m of consecutive composite sums k + j*(j+1)/2, j = 1, ..., m is a new maximum.

4, 8, 9, 15, 24, 90, 105, 114, 225, 264, 300, 945, 5349, 7035, 11739, 17280, 35475, 46914, 190365, 351645, 603054, 1209900, 3146220, 3279864, 6407664, 26447649, 115192665, 408291345, 1080430119, 1298351109, 6459163344, 7731193299, 8096124894, 8884256514, 18927105834

Offset

1,1

Comments

a(57) > 1.2 * 10^14.

Links

Karl-Heinz Hofmann and Hugo Pfoertner, Table of n, a(n) for n = 1..56

IBM Research, Composite Sequences, Ponder This Challenge March 2024.

Crossrefs

A371000 gives the corresponding counts m.

Cf. A000217, A371001, A371002.

Sequence in context: A161542 A131195 A020217 * A329728 A141066 A018196

Adjacent sequences: A370996 A370997 A370998 * A371000 A371001 A371002

Keyword

nonn

Author

Karl-Heinz Hofmann and Hugo Pfoertner, Mar 09 2024

Extensions

a(43) in b-file corrected by Kebbaj Mohamed Reda, May 29 2024

Status

approved