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Numbers that are the sum of 17 but no fewer nonzero fourth powers.
6

%I #27 Aug 27 2023 19:42:50

%S 47,62,77,127,142,157,207,222,237,287,302,317,367,382,397,447,462,477,

%T 527,542,557,607,622,687,702,752,767,782,847,862,927,942,992,1007,

%U 1022,1087,1102,1167,1182,1232,1247,1327,1407,1487,1567,1647,1727,1807,2032

%N Numbers that are the sum of 17 but no fewer nonzero fourth powers.

%C a(65) = 13792 is the last term of this sequence; see A099591 for further references.

%H T. D. Noe, <a href="/A046048/b046048.txt">Table of n, a(n) for n= 1..65</a> (full sequence)

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/BiquadraticNumber.html">Biquadratic Number</a>.

%e 62 is the sum of 17 4th powers and no fewer, so 62 is a term.

%e 63 is the sum of 18 4th powers and no fewer, so 63 is not a term, although it is a term of A099591.

%t lim = 2100; f[n_] := f[n] = (k = 0; While[k++; k <= 17 && PowersRepresentations[n, k, 4] == {}]; k); Select[Range[lim], f[#] == 17 &] (* _Jean-François Alcover_, Sep 08 2011 *)

%Y Cf. A000583, A002377, A046047, A099591.

%K nonn,fini,full,nice

%O 1,1

%A _Eric W. Weisstein_

%E More terms from Arlin Anderson (starship1(AT)gmail.com)