A138990 - OEIS

A138990

a(n) = Frobenius number for 4 successive primes = F[p(n), p(n+1), p(n+2), p(n+3)].

1, 4, 9, 23, 42, 67, 83, 101, 125, 199, 262, 335, 367, 393, 492, 593, 704, 807, 873, 990, 817, 950, 1101, 1353, 2039, 2624, 2371, 1494, 1431, 1640, 2927, 2368, 2875, 2667, 3570, 3348, 3625, 3918, 4531, 3816, 4831, 4543, 9357, 4819, 4131, 6611, 5735, 10483

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OFFSET

1,2

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

a(3)=23 because 23 is the largest number k such that the equation 7*x_1 + 11*x_2 + 13*x_3 + 17*x + 4 = k has no solution for any nonnegative x_i (in other words, for every k > 23 there exist one or more solutions).

MATHEMATICA

Table[FrobeniusNumber[{Prime[n], Prime[n + 1], Prime[n + 2], Prime[n + 3]}], {n, 1, 100}]

FrobeniusNumber/@Partition[Prime[Range[60]], 4, 1] (* Harvey P. Dale, Nov 23 2014 *)

CROSSREFS

Frobenius numbers for k successive primes: A037165 (k=2), A138989 (k=3), this sequence (k=4), A138991 (k=5), A138992 (k=6), A138993 (k=7), A138994 (k=8).

Cf. A028387, A079326, A138985, A138986, A138987, A138988.

Sequence in context: A060250 A138991 A361002 * A014543 A343676 A131607

Adjacent sequences: A138987 A138988 A138989 * A138991 A138992 A138993

KEYWORD

nonn

AUTHOR

Artur Jasinski, Apr 05 2008

EXTENSIONS

Definition corrected by Harvey P. Dale, Aug 15 2014

STATUS

approved