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A373611
Positive integers that cannot be written as a sum of a practical number and a nonagonal number.
1
14, 22, 23, 34, 35, 38, 46, 53, 59, 68, 71, 92, 98, 116, 122, 125, 138, 148, 173, 188, 227, 230, 245, 247, 259, 278, 290, 323, 338, 356, 359, 407, 422, 470, 499, 548, 557, 593, 628, 638, 688, 692, 710, 722, 743, 797, 818, 893, 902, 917, 947, 962, 983, 1013
OFFSET
1,1
COMMENTS
Somu and Tran (2024) conjectured that there are finitely many such integers. It was also conjectured that 325808 is the largest such integer. This conjecture was checked up to 10^8.
LINKS
Sai Teja Somu and Duc Van Khanh Tran, On sums of practical numbers and polygonal numbers, Journal of Integer Sequences, 27(5), 2024.
CROSSREFS
Sequence in context: A166628 A199250 A199195 * A291618 A266214 A113190
KEYWORD
nonn,hard
AUTHOR
Duc Van Khanh Tran, Jun 10 2024
STATUS
approved