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A100291
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Numbers of the form a^4 + b^3 with a, b > 0.
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12
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2, 9, 17, 24, 28, 43, 65, 80, 82, 89, 108, 126, 141, 145, 206, 217, 232, 257, 264, 283, 297, 320, 344, 359, 381, 424, 472, 513, 528, 593, 599, 626, 633, 652, 689, 730, 745, 750, 768, 810, 841, 968, 985, 1001, 1016, 1081, 1137, 1256, 1297, 1304, 1323, 1332
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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lst={}; Do[p=a^4+b^3; If[p<2000, AppendTo[lst, p]], {a, 64}, {b, 256}]; Union[lst]
With[{nn=20}, Select[Union[#[[1]]^4+#[[2]]^3&/@Tuples[Range[20], 2]], #<= nn^3+1&]] (* Harvey P. Dale, May 27 2020 *)
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PROG
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(PARI) is(n)=for(a=1, sqrtnint(n-1, 4), ispower(n-a^4, 3) && return(a)) \\ Returns a > 0 if n is in the sequence, or 0 otherwise. - M. F. Hasler, Apr 25 2018
(PARI) list(lim)=my(v=List()); for(b=1, sqrtnint(lim\=1, 3), my(b3=b^3); for(a=1, sqrtnint(lim-b3, 4), listput(v, a^4+b3))); Set(v) \\ Charles R Greathouse IV, Jul 26 2021
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CROSSREFS
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Cf. A100271 (primes of the form a^4 + b^3).
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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