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A256091 Numbers D such that D^2 = A^3 + B^4 + C^5 for some positive integers A, B, C. 9
5, 7, 9, 11, 17, 23, 25, 33, 38, 45, 55, 72, 79, 89, 95, 96, 99, 100, 103, 105, 117, 133, 137, 163, 171, 213, 218, 220, 237, 239, 240, 248, 255, 257, 282, 303, 305, 320, 347, 355, 362, 375, 384, 393, 407, 408, 411, 459, 475, 503, 506, 513, 525, 539, 540, 567, 581, 613, 616, 657, 659, 660, 751, 752, 761, 792, 796, 808, 824, 833 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

(8^n*(4^n+8); n = 0, 1, 2, ...) is an infinite subsequence of the subsequence A256613: see that entry for more details.

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

EXAMPLE

(A, B, C) = (1, 4, 2): 1^3 + 4^4 + 2^5 = 1 + 256 + 32 = 289 = 17^2, so 17 is a term.

PROG

(PARI) for(D=3, 9999, for(C=1, sqrtn(D^2-2, 5), for(B=1, sqrtn(D^2-C^5-1, 4), ispower(D^2-C^5-B^4, 3)&&print1(D", "))))

(PARI) for(D=3, 9999, ok = 0; for(C=1, sqrtn(D^2-2, 5), for(B=1, sqrtn(D^2-C^5-1, 4), ispower(D^2-C^5-B^4, 3)&&(ok=1)&&print1(D", "); if (ok, break)); if (ok, break))) \\ Michel Marcus, Apr 26 2015

CROSSREFS

Cf. A180241, A180242, A256613, A255830.

Sequence in context: A076190 A028885 A228233 * A229064 A024910 A283771

Adjacent sequences:  A256088 A256089 A256090 * A256092 A256093 A256094

KEYWORD

nonn

AUTHOR

M. F. Hasler, Apr 04 2015

EXTENSIONS

Inserted a(5)=17 and removed the doublet 525 by Lars Blomberg, Apr 26 2015

STATUS

approved

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Last modified May 20 03:37 EDT 2022. Contains 353851 sequences. (Running on oeis4.)