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A130833
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Sums of two or more distinct 4th powers of primes.
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1
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97, 641, 706, 722, 2417, 2482, 2498, 3026, 3042, 3107, 3123, 14657, 14722, 14738, 15266, 15282, 15347, 15363, 17042, 17058, 17123, 17139, 17667, 17683, 17748, 17764, 28577, 28642, 28658, 29186, 29202, 29267, 29283, 30962, 30978, 31043, 31059, 31587, 31603
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| This is to cubes and A030078 as A192926 is to 4th powers and A030514. The subsequence of primes which are sums of two or more distinct 4th powers of primes begins 97, 641, 2417.
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FORMULA
| {A030078(i) + A030078(j) for i not equal to j} UNION {A030078(i) + A030078(j) + A030078(k) for i not equal to j not equal to k} UNION {A030078(i) + A030078(j) + A030078(k) + A030078(L) for i not equal to j not equal to k not equal to L}...
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EXAMPLE
| a(1) = 97 = 2^4 + 3^4.
a(2) = 641 = 2^4 + 5^4.
a(3) = 706 = 3^4 + 5^4.
a(4) = 722 = 2^4 + 3^4 + 5^4.
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MATHEMATICA
| nn=6; t = Sort@ Flatten@ Table[ n^4, {n, Prime@ Range@ nn}]; Select[Sort[
Plus @@@ Subsets[t, {2, nn}]], # < Prime[nn-1]^4 + Prime[nn]^4 &] (* Robert G. Wilson v, July 22 2011 *)
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CROSSREFS
| Cf. A000040, A000583, A030514, A192926.
Sequence in context: A142765 A144130 A144131 * A130873 A193411 A094479
Adjacent sequences: A130830 A130831 A130832 * A130834 A130835 A130836
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KEYWORD
| nonn,easy
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AUTHOR
| Jonathan Vos Post (jvospost3(AT)gmail.com), Jul 21 2011
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