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A069762 Frobenius number of the numerical semigroup generated by three consecutive pyramidal numbers. 1
51, 191, 609, 1324, 2813, 4711, 8576, 13894, 23319, 34165, 51661, 71126, 100529, 136239, 187543, 241586, 321251, 404839, 516704, 645358 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

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 pyramidal 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=0..19.

EXAMPLE

a(2)=51 because 51 is not a nonnegative linear combination of 5, 14 and 30, but all integers greater than 51 are.

CROSSREFS

Cf. A000330, A037165, A059769, A069755-A069764.

Sequence in context: A257352 A008883 A327624 * A245829 A031431 A157365

Adjacent sequences:  A069759 A069760 A069761 * A069763 A069764 A069765

KEYWORD

easy,nonn

AUTHOR

Victoria A Sapko (vsapko(AT)canes.gsw.edu), Apr 18 2002

STATUS

approved

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Last modified November 19 06:34 EST 2019. Contains 329310 sequences. (Running on oeis4.)