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A373615 Positive integers that cannot be written as a sum of a practical number and an 11-gonal number. 1
10, 11, 14, 22, 26, 44, 45, 52, 63, 68, 69, 87, 92, 93, 116, 117, 152, 164, 172, 182, 188, 194, 233, 242, 243, 247, 248, 259, 279, 327, 374, 377, 402, 434, 482, 517, 579, 629, 712, 752, 759, 777, 824, 852, 934, 997, 1209, 1238, 1287, 1314, 1454, 1602, 1804 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Somu and Tran (2024) conjectured that there are finitely many such integers. It was also conjectured that 105712 is the largest such integer. This conjecture was checked up to 10^8.
LINKS
Duc Van Khanh Tran, Table of n, a(n) for n = 1..68
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: A144980 A261713 A244283 * A373617 A043583 A043773
KEYWORD
nonn,hard
AUTHOR
Duc Van Khanh Tran, Jun 11 2024
STATUS
approved

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Last modified July 21 09:38 EDT 2024. Contains 374472 sequences. (Running on oeis4.)