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A069761 Frobenius number of the numerical semigroup generated by four consecutive tetrahedral numbers. 1

%I

%S 41,249,253,853,1243,1571,2619,5059,5357,9437,11801,13609,18327,27607,

%T 28919,41951,49169,54473,67253,90573,94051,124099,140347,152027,

%U 178989,226141,233369,291089,321839,343639,392631,475999,488993,587633,639653,676181,756779

%N Frobenius number of the numerical semigroup generated by four consecutive tetrahedral numbers.

%C 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 four consecutive tetrahedral numbers are relatively prime, they generate a numerical semigroup with a Frobenius number.

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

%H Harvey P. Dale, <a href="/A069761/b069761.txt">Table of n, a(n) for n = 2..100</a>

%e a(2)=41 because 41 is not a nonnegative linear combination of 4, 10, 20 and 35, but all integers greater than 43 are.

%t FrobeniusNumber/@Partition[Binomial[Range[2,50]+2,3],4,1] (* _Harvey P. Dale_, Jan 22 2012 *)

%Y Cf. A000292, A037165, A059769, A069755-A069764.

%K easy,nonn

%O 2,1

%A Victoria A Sapko (vsapko(AT)canes.gsw.edu), Apr 09 2002

%E Sequence terms corrected and extended by Harvey P. Dale, Jan 22 2012

%E Offset corrected and example corrected by Harvey P. Dale, Jan 24 2012

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Last modified August 9 01:35 EDT 2020. Contains 336310 sequences. (Running on oeis4.)