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A363522
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Number of integers k such that there are exactly n distinct numbers j with k^2 < j < (k+1)^2 which can be expressed as sum of two squares.
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3
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1, 1, 2, 1, 2, 1, 3, 1, 2, 1, 2, 3, 2, 1, 1, 3, 2, 2, 1, 3, 3, 1, 3, 1, 2, 1, 4, 2, 1, 3, 1, 3, 1, 3, 1, 4, 1, 3, 2, 1, 1, 4, 1, 4, 2, 3, 0, 2, 3, 3, 3, 2, 2, 2, 1, 0, 3, 5, 1, 4, 1, 4, 0, 2, 2, 3, 4, 1, 1, 3, 3, 0, 5, 1, 4, 1, 2, 1, 3, 4, 0, 3, 3, 2, 2, 4, 0, 3
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OFFSET
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0,3
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COMMENTS
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Number of occurrences of n in A077773.
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LINKS
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EXAMPLE
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a(0) = 1, since A077773(k) = 0 at the single index k = 0.
a(6) = 3, since A077773(k) = 6 for these 3 indices: k = 8, 9, and 11.
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PROG
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(Python)
from sympy import factorint
s = 0
for k in range(n>>1, ((n+1)**2<<1)+1):
c = 0
for m in range(k**2+1, (k+1)**2):
if all(p==2 or p&3==1 or e&1^1 for p, e in factorint(m).items()):
c += 1
if c>n:
break
if c==n:
s += 1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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