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A137366 Subsequence of A137365 where it is possible to choose p1, p2, p3 so that p1+p2+p3 = prime. 3
1483, 5381, 6271, 7229, 9181, 11897, 13103, 13841, 14489, 17107, 20357, 25747, 26711, 27917, 30161, 30259, 31247, 32579, 36677, 36899, 36901, 42083, 48817, 54181, 55511, 55691, 56377, 57637, 64151, 66347, 69389, 75167, 76031, 76123 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
36161 is the first number that is in A137365 but not in the present sequence. See A138556.
LINKS
R. J. Mathar and Vincenzo Librandi, Table of n, a(n) for n = 1..350 (first 44 terms from R. J. Mathar)
EXAMPLE
1483=3^3+5^3+11^3, 3+5+11=17;
7229=3^3+7^3+19^3, 3+7+19=29.
MATHEMATICA
Array[r, 99]; Array[y, 99]; For[i = 0, i < 10^2, r[i] = y[i] = 0; i++ ]; z = 4^2; n = 0; For[i1 = 1, i1 < z, a = Prime[i1]; a2 = a^3; For[i2 = i1 + 1, i2 < z, b = Prime[i2]; b2 = b^3; For[i3 = i2 + 1, i3 < z, c = Prime[i3]; c2 = c^3; p = a2 + b2 + c2; p3 = a + b + c; If[PrimeQ[p] && PrimeQ[p3], Print[a2, " + ", b2, " + ", c2, " = ", p, "; ", a, " + ", b, " + ", c, " = ", p3]; n++; r[n] = p]; i3++ ]; i2++ ]; i1++ ]; Sort[Array[r, 71]]
lst = {}; Do[q = Prime@a; r = Prime@b; s = Prime@c; p = q^3 + r^3 + s^3; t = q + r + s; If[PrimeQ@p && PrimeQ@t, AppendTo[lst, p]], {a, 14}, {b, a - 1}, {c, b - 1}]; Take[Sort@lst, 35] (* Robert G. Wilson v, Apr 13 2008 *)
CROSSREFS
Sequence in context: A035864 A255087 A137365 * A045008 A327880 A257713
KEYWORD
nonn
AUTHOR
Vladimir Joseph Stephan Orlovsky, Apr 09 2008, Apr 14 2008
STATUS
approved

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Last modified June 24 02:53 EDT 2024. Contains 373661 sequences. (Running on oeis4.)