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A069758 Frobenius number of the numerical semigroup generated by three consecutive hexagonal numbers. 0
65, 377, 395, 797, 1589, 6029, 3347, 4571, 6035, 10997, 10979, 12212, 19409, 47246, 24023, 29003, 35357, 52112, 50603, 50411, 73049, 158207, 78155, 90203, 102005, 144443, 138467, 131474, 183077 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,1
COMMENTS
The Frobenius number of a numerical semigroup generated by relatively prime integers a_1,...,a_n is the largest positive integer that is not a nonnegative linear combination of a_1,...,a_n. Since three consecutive hexagonal numbers are relatively prime, they generate a numerical semigroup with a Frobenius number.
REFERENCES
R. Fröberg, C. Gottlieb and R. Häggkvist, "On numerical semigroups", Semigroup Forum, 35 (1987), 63-83 (for definition of Frobenius number).
LINKS
EXAMPLE
a(2)=65 because 65 is not a nonnegative linear combination of 6, 15 and 28, but all integers greater than 65 are.
MATHEMATICA
FrobeniusNumber/@Partition[Table[n(2n-1), {n, 2, 35}], 3, 1] (* Harvey P. Dale, Jul 25 2011 *)
CROSSREFS
Sequence in context: A319617 A300162 A211259 * A116678 A218845 A219424
KEYWORD
easy,nonn
AUTHOR
Victoria A Sapko (vsapko(AT)canes.gsw.edu), Apr 08 2002
STATUS
approved

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Last modified June 17 21:09 EDT 2024. Contains 373464 sequences. (Running on oeis4.)