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A116905
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Number of partitions of n-th 3-almost prime into 2 squares.
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0
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1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 2, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 2, 2, 0, 0, 1, 1, 0, 1, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,11
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COMMENTS
| See also A000161 Number of partitions of n into 2 squares (when order does not matter and zero is allowed).
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FORMULA
| a(n) = A000161(A014612(n)).
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EXAMPLE
| a(1) = 1 because A014612(1) = 8 = 2^2 + 2^2, the unique sum of squares.
a(2) = 0 because A014612(2) = 12 has no decomposition into sum of 2 squares because it has a prime factor p == 3 (mod 4) with an odd power.
a(11) = 2 because A014612(11) = 50 = 2*5^2 = 1^2 + 7^2 = 5^2 + 5^2.
a(30) = 2 because A014612(30) = 125 = 5^3 = 2^2 + 11^2 = 5^2 + 1^0.
a(31) = 2 because A014612(31) = 130 = 2*5*13 = 3^2 + 11^2 = 7^2 + 9^2.
a(39) = 2 because A014612(39) = 170 = 2*5*17 = 1^2 + 13^2 = 7^2 + 11^2.
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CROSSREFS
| Cf. A000161, A014612.
Sequence in context: A184616 A065860 A010110 * A115079 A025435 A186714
Adjacent sequences: A116902 A116903 A116904 * A116906 A116907 A116908
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KEYWORD
| easy,nonn
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AUTHOR
| Jonathan Vos Post (jvospost3(AT)gmail.com), Mar 15 2006
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