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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A378647 Dirichlet convolution of A074206 and A103977, where A074206 is the number of ordered factorizations of n, and A103977 is the Zumkeller deficiency of n.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 16, 13, 14, 15, 16, 17, 22, 19, 22, 21, 22, 23, 40, 25, 26, 27, 28, 29, 42, 31, 32, 33, 34, 35, 64, 37, 38, 39, 52, 41, 54, 43, 44, 45, 46, 47, 96, 49, 50, 51, 52, 53, 70, 55, 64, 57, 58, 59, 126, 61, 62, 63, 64, 65, 78, 67, 68, 69, 74, 71, 176, 73, 74, 75, 76, 77, 90, 79, 120, 81
Offset: 1

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Author

Antti Karttunen, Dec 03 2024

Keywords

Comments

Möbius transform of A378648, which is the Dirichlet convolution of A067824 and A103977.

Crossrefs

Cf. A000027, A008683, A067824, A074206, A103977, A263837, A378648 (inverse Möbius transform), A378649 (Möbius transform), A378650 [= a(n)-n], A378655 (Dirichlet inverse).

Programs

Formula

a(n) = Sum_{d|n} A074206(d)*A103977(n/d).
a(n) = Sum_{d|n} A008683(d)*A378648(n/d).
a(n) = Sum_{d|n} A067824(d)*A378644(n/d).
a(n) = A378650(n)+n, with a(n) = n if and only if n is a non-abundant number (A263837).