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A004905
Numbers that are the sum of at most 10 nonzero 10th powers.
2
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031, 1032, 1033, 2048, 2049, 2050, 2051, 2052, 2053, 2054, 2055, 2056, 3072, 3073, 3074, 3075, 3076, 3077, 3078, 3079, 4096, 4097, 4098, 4099, 4100, 4101, 4102, 5120, 5121, 5122, 5123
OFFSET
1,3
LINKS
MAPLE
b:= proc(n, i, t) option remember; n=0 or i>0 and t>0
and (b(n, i-1, t) or i^10<=n and b(n-i^10, i, t-1))
end:
a:= proc(n) option remember; local k;
for k from 1+ `if`(n=1, -1, a(n-1))
while not b(k, iroot(k, 10), 10) do od; k
end:
seq(a(n), n=1..60); # Alois P. Heinz, Sep 16 2016
MATHEMATICA
b[n_, i_, t_] := b[n, i, t] = n == 0 || i > 0 && t > 0 && (b[n, i - 1, t] || i^10 <= n && b[n - i^10, i, t - 1]);
a[n_] := a[n] = (For[k = 1 + If[n == 1, -1, a[n - 1]], !b[k, k^(1/10) // Floor, 10], k++]; k);
Array[a, 60] (* Jean-François Alcover, Apr 06 2017, after Alois P. Heinz *)
CROSSREFS
Column k=10 of A336820.
Sequence in context: A326302 A004883 A004894 * A004916 A120126 A062399
KEYWORD
nonn
EXTENSIONS
More terms from Alois P. Heinz, Sep 16 2016
STATUS
approved