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A371968
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Numbers k that are not the sum of distinct squares that do not divide k.
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1
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1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 26, 27, 28, 30, 31, 32, 33, 35, 36, 37, 39, 40, 42, 43, 44, 46, 47, 48, 50, 51, 54, 55, 56, 57, 59, 60, 63, 64, 66, 67, 68, 71, 72, 75, 76, 79, 80, 82, 84, 88, 91, 92, 95, 96, 99, 104, 107, 108, 111, 112, 120, 124, 127, 128, 132, 135, 140, 144, 147, 148, 156, 160, 168, 172, 176, 184, 188, 192, 200, 216, 224, 252, 256, 288, 300, 432
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history;
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internal format)
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OFFSET
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1,2
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COMMENTS
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Numbers k such that A294266(k) = 0.
No other terms <= 100000.
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LINKS
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EXAMPLE
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a(20) = 21 is a term because the only way to write 21 as the sum of distinct squares is 1^2 + 2^2 + 4^2, but 21 is divisible by 1^2.
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MAPLE
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filter:= proc(n) local P, k, x;
P:= 1;
for k from 2 to floor(sqrt(n)) do
if n mod k^2 = 0 then next fi;
P:= series(P*(1+x^(k^2)), x, n+1);
if coeff(P, x, n) > 0 then return false fi;
od;
true
end proc:
select(filter, [$1..500]);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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More terms than usual in the DATA section, because these are probably all the terms.
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STATUS
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approved
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