cp's OEIS Frontend

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.

A277992 b(n, 2) where b(n, m) is defined by expansion of ((Product_{k>=1} (1 - x^(prime(n)*k))/(1 - x^k)^prime(n)) - 1)/prime(n) in powers of x.

Original entry on oeis.org

2, 3, 4, 5, 7, 8, 10, 11, 13, 16, 17, 20, 22, 23, 25, 28, 31, 32, 35, 37, 38, 41, 43, 46, 50, 52, 53, 55, 56, 58, 65, 67, 70, 71, 76, 77, 80, 83, 85, 88, 91, 92, 97, 98, 100, 101, 107, 113, 115, 116, 118, 121, 122, 127, 130, 133, 136, 137, 140, 142, 143, 148, 155, 157
Offset: 1

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Author

Seiichi Manyama, Nov 07 2016

Keywords

Comments

c(n, m) is defined by expansion of (Product_{k>=1} 1/(1 - x^k)^prime(n))/prime(n) in powers of x.
b(n, 2) = c(n, 2) for n > 1.

Examples

			a(1) = b(1, 2) = A014968(2) = 2.
a(2) = b(2, 2) = A277968(2) = c(2, 2) = A000716(2)/3 = 3.
a(3) = b(3, 2) = A277974(2) = c(3, 2) = A023004(2)/5 = 4.
a(4) = b(4, 2) = A160549(2) = c(4, 2) = A023006(2)/7 = 5.
a(5) = b(5, 2) = A277912(2) = c(5, 2) = A023010(2)/11 = 7.
		

Crossrefs

Expansion of Product_{k>=1} 1/(1 - x^k)^prime(n): A000712 (n=1), A000716 (n=2), A023004 (n=3), A023006 (n=4), A023010 (n=5).

Formula

a(n) = A098090(n - 1) = (prime(n) + 3)/2 for n > 1.