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A282380 Number of ways to write n as a sum of two unordered nonsquarefree numbers. 1
0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 2, 1, 1, 0, 2, 1, 1, 0, 3, 1, 1, 1, 3, 2, 1, 1, 4, 2, 2, 1, 6, 2, 1, 1, 5, 2, 1, 2, 5, 3, 1, 1, 6, 3, 2, 1, 7, 4, 4, 1, 7, 4, 4, 2, 7, 4, 3, 3, 8, 4, 3, 3, 9, 4, 4, 2, 12, 4, 4, 3, 10, 5, 3, 4, 10, 6, 3, 3, 11, 5, 3, 3, 12, 5, 6, 3, 11, 6, 5, 4, 12, 5, 5, 7, 14, 5, 6, 5, 14, 5, 6 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,16

LINKS

Altug Alkan, Table of n, a(n) for n = 1..10000

EXAMPLE

a(16) = 2 because 16 = 4 + 12 and 16 = 8 + 8 are only corresponding solutions.

PROG

(PARI) a(n) = sum(k=1, n\2, !issquarefree(k) && !issquarefree(n-k));

CROSSREFS

Cf. A013929, A071068.

Sequence in context: A219052 A060826 A078134 * A083661 A029369 A255315

Adjacent sequences:  A282377 A282378 A282379 * A282381 A282382 A282383

KEYWORD

nonn

AUTHOR

Altug Alkan, Feb 13 2017

STATUS

approved

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Last modified June 14 14:21 EDT 2021. Contains 345025 sequences. (Running on oeis4.)