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A347822
Number of ways to write n as the sum of 2 balanced numbers.
0
0, 1, 1, 2, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 2, 2, 2, 2, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 2, 1, 1, 0, 0, 1, 1, 1, 2, 2, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 2, 1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 2, 2, 2, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 0, 3, 1, 1, 0, 0, 0, 1, 1, 1, 1
OFFSET
1,4
COMMENTS
A balanced number k is a number such that phi(k) | sigma(k).
FORMULA
a(n) = Sum_{k=1..floor(n/2)} c(k) * c(n-k), where c = A351114.
EXAMPLE
a(84) = 3; 84 = 78+6 = 70+14 = 42+42.
CROSSREFS
Cf. A020492 (balanced numbers), A351114.
Sequence in context: A237837 A365126 A168509 * A079635 A037909 A181506
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Feb 01 2022
STATUS
approved