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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. Froberg, C. Gottlieb and R. Haggkvist, "On numerical semigroups", Semigroup Forum, 35 (1987), 63-83 (for definition of Frobenius number).

LINKS

Table of n, a(n) for n=2..30.

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

Cf. A000384, A037165, A059769, A069755-A069764.

Sequence in context: A319617 A300162 A211259 * A116678 A218845 A219424

Adjacent sequences:  A069755 A069756 A069757 * A069759 A069760 A069761

KEYWORD

easy,nonn

AUTHOR

Victoria A Sapko (vsapko(AT)canes.gsw.edu), Apr 08 2002

STATUS

approved

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Last modified December 5 17:42 EST 2019. Contains 329768 sequences. (Running on oeis4.)