A373665 Positive integers that cannot be written as a sum of a practical number and a 16-gonal number.

10, 11, 14, 15, 23, 26, 27, 35, 38, 39, 45, 50, 59, 62, 68, 71, 74, 83, 86, 95, 98, 102, 103, 107, 110, 114, 115, 119, 122, 131, 134, 137, 138, 139, 143, 155, 158, 159, 164, 167, 170, 174, 179, 182, 183, 186, 190, 191, 194, 202, 203, 206, 215, 219, 227, 230

Offset

1,1

Comments

Somu and Tran (2024) proved that there are infinitely many such integers. More generally, infinitely many positive integers cannot be written as a sum of a practical number and an s-gonal number if s is congruent to 4 modulo 12.

Links

Duc Van Khanh Tran, Table of n, a(n) for n = 1..10000

Sai Teja Somu and Duc Van Khanh Tran, On sums of practical numbers and polygonal numbers, Journal of Integer Sequences, 27(5), 2024.

Crossrefs

Cf. A005153, A051868.

Sequence in context: A298365 A373634 A373633 * A373646 A335237 A214864

Adjacent sequences: A373662 A373663 A373664 * A373666 A373667 A373668

Keyword

nonn

Author

Duc Van Khanh Tran, Jun 12 2024

Status

approved