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Numbers that are the sum of 7 positive 10th powers.
31

%I #21 Aug 04 2020 14:57:45

%S 7,1030,2053,3076,4099,5122,6145,7168,59055,60078,61101,62124,63147,

%T 64170,65193,118103,119126,120149,121172,122195,123218,177151,178174,

%U 179197,180220,181243,236199,237222,238245,239268,295247,296270,297293,354295,355318,413343,1048582

%N Numbers that are the sum of 7 positive 10th powers.

%H David A. Corneth, <a href="/A004807/b004807.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from T. D. Noe)

%e From _David A. Corneth_, Aug 03 2020: (Start)

%e 1129904068 is in the sequence as 1129904068 = 2^10 + 2^10 + 2^10 + 7^10 + 7^10 + 7^10 + 7^10.

%e 1357385795 is in the sequence as 1357385795 = 2^10 + 2^10 + 3^10 + 3^10 + 4^10 + 7^10 + 8^10.

%e 3831882028 is in the sequence as 3831882028 = 1^10 + 3^10 + 4^10 + 4^10 + 6^10 + 7^10 + 9^10. (End)

%t k = 7; p = 10; amax = 10^6; bmax = amax^(1/p) // Ceiling; Clear[b]; b[0] = 1; Select[Table[Total[Array[b, k]^p], {b[1], b[0], bmax}, Evaluate[ Sequence @@ Table[{b[j], b[j-1], bmax}, {j, 1, k}]]] //Flatten // Union, # <= amax&] (* _Jean-François Alcover_, Jul 19 2017 *)

%Y Cf. A008454 (tenth powers).

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_