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URL: https://oeis.org/A018821

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A018821
n is the sum of k nonzero squares for all 2 <= k <= n-14.
1
17, 18, 26, 34, 45, 50, 53, 61, 65, 68, 72, 73, 74, 82, 89, 90, 97, 98, 101, 104, 106, 109, 113, 116, 117, 122, 125, 136, 137, 145, 146, 149, 153, 157, 162, 164, 169, 170, 173, 178, 180, 181, 185, 193, 194, 197, 200, 202, 205, 212, 218, 221, 225, 226, 229, 233, 234, 241
OFFSET
1,1
COMMENTS
Every n > 19 is the sum of k nonzero squares for all 6 <= k <= n-14. - Robert Israel, Apr 09 2017
MAPLE
N:= 1000: # to get all terms <= N
A:= {$16..N}:
S:= {seq(i^2, i=1..floor(sqrt(N)))}:
SS:= S:
for k from 2 to 6 do
SS:= select(`<=`, {seq(seq(s+t, s=S), t=SS)}, N):
A := select(`<`, A, k+14) union (A intersect SS);
od:
sort(convert(A, list)); # Robert Israel, Apr 09 2017
CROSSREFS
Sequence in context: A295487 A308888 A084379 * A255923 A226673 A151978
KEYWORD
nonn
STATUS
approved