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A138993 a(n) = Frobenius number for 7 successive primes = F[p(n), p(n+1), p(n+2), p(n+3), p(n+4), p(n+5), p(n+6)]. 11

%I #14 Jan 27 2023 13:35:28

%S 1,4,9,16,27,41,49,63,102,114,169,187,203,221,304,328,409,441,465,495,

%T 525,559,769,811,867,907,826,854,886,938,1403,1451,1505,1555,1786,

%U 1838,1741,2125,2193,2605,2325,2005,2479,2318,2362,2637,3402,4012,3857,3666

%N a(n) = Frobenius number for 7 successive primes = F[p(n), p(n+1), p(n+2), p(n+3), p(n+4), p(n+5), p(n+6)].

%e a(4)=16 because 16 is the largest number k such that the equation 7*x_1 + 11*x_2 + 13*x_3 + 17*x_4 + 19*x_5 + 23*x_6 + 29*x_7 = k has no solution for any nonnegative x_i (in other words, for every k > 16 there exist one or more solutions).

%t Table[FrobeniusNumber[{Prime[n],Prime[n + 1], Prime[n + 2], Prime[n + 3], Prime[n + 4], Prime[n + 5], Prime[n + 6]}], {n, 1, 100}]

%t FrobeniusNumber/@Partition[Prime[Range[100]],7,1] (* _Harvey P. Dale_, Aug 15 2014 *)

%Y Frobenius numbers for k successive primes: A037165 (k=2), A138989 (k=3), A138990 (k=4), A138991 (k=5), A138992 (k=6), this sequence (k=7), A138994 (k=8).

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

%K nonn

%O 1,2

%A _Artur Jasinski_, Apr 05 2008

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Last modified May 12 22:15 EDT 2024. Contains 372496 sequences. (Running on oeis4.)