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.

A240146 Number of partitions of n into distinct parts, where the difference between the number of odd parts and the number of even parts is 10.

Original entry on oeis.org

1, 0, 1, 0, 2, 0, 3, 0, 5, 0, 7, 0, 11, 0, 15, 0, 22, 0, 30, 0, 42, 0, 55, 1, 75, 2, 97, 4, 128, 7, 164, 12, 212, 19, 267, 30, 340, 45, 423, 67, 530, 97, 653, 139, 807, 195, 984, 271, 1204, 370, 1456, 501, 1763, 670, 2117, 889, 2543, 1167, 3032, 1522, 3618
Offset: 100

Views

Author

Alois P. Heinz, Apr 02 2014

Keywords

Comments

With offset 110 number of partitions of n into distinct parts, where the difference between the number of odd parts and the number of even parts is -10.

Examples

			a(104) = 2: [23,17,15,13,11,9,7,5,3,1], [21,19,15,13,11,9,7,5,3,1].
a(125) = 2: [23,19,17,15,13,11,9,7,5,3,2,1], [21,19,17,15,13,11,9,7,5,4,3,1].
		

Crossrefs

Column k=10 of A240021.

Programs

  • Maple
    b:= proc(n, i, t) option remember; `if`(n>i*(i+1)/2 or
          abs(t)>n, 0, `if`(n=0, 1, b(n, i-1, t)+
          `if`(i>n, 0, b(n-i, i-1, t+(2*irem(i, 2)-1)))))
        end:
    a:= n-> b(n$2, -10):
    seq(a(n), n=100..160);

Formula

a(n) = [x^n y^10] Product_{i>=1} 1+x^i*y^(2*(i mod 2)-1).