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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.

A361665 Number of ordered factorizations of p_1^x_1 * ... * p_k^x_k, where (x_1, ..., x_k) is the partition with Heinz number n and p_1, ..., p_k are distinct primes.

Original entry on oeis.org

1, 1, 2, 3, 4, 8, 8, 13, 26, 20, 16, 44, 32, 48, 76, 75, 64, 176, 128, 132, 208, 112, 256, 308, 252, 256, 818, 368, 512, 604, 1024, 541, 544, 576, 768, 1460, 2048, 1280, 1376, 1076, 4096, 1888, 8192, 976, 3172, 2816, 16384, 2612, 2568, 2316, 3392, 2496, 32768
Offset: 1

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Author

Pontus von Brömssen, Mar 20 2023

Keywords

Comments

Also, a(n) is the number of paths from (0, ..., 0) to P in which each step adds a nonnegative integer to each coordinate (and a positive number to at least one coordinate), where P is the partition with Heinz number n.

Examples

			The partition with Heinz number 6 is (1,2), and p^1*q^2 has 8 ordered factorizations, where p and q are distinct primes, so a(6) = 8. With p = 3 and q = 2, for example, we have the 8 = A074206(12) factorizations 12 = 2*6 = 3*4 = 4*3 = 6*2 = 2*2*3 = 2*3*2 = 3*2*2.
		

Crossrefs

Formula

a(n) = A074206(A181821(n)).