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.

A091109 Number of occurrences of smallest prime factor in all partitions of n-th composite number: a(n)=A066633(A002808(n), A056608(n)).

Original entry on oeis.org

3, 8, 19, 15, 41, 83, 160, 122, 295, 526, 911, 683, 1538, 2540, 853, 4115, 3050, 6551, 10269, 15873, 11664, 24222, 8415, 36532, 54509, 39784, 80524, 117862, 171036, 124143, 246211, 351769, 72718, 499042, 360550, 703268, 984857, 353996
Offset: 1

Views

Author

Reinhard Zumkeller, Feb 22 2004

Keywords

Examples

			n=2: A002808(2)=6=2*3 has A000041(6)=11 partitions: 6 = 5+1 = 4+2 = 4+1+1 = 3+3 = 3+2+1 = 3+1+1+1 = 2+2+2 = 2+2+1+1 = 2+1+1+1+1 = 1+1+1+1+1+1, 2 occurs 8 times, therefore a(2)=8.
		

Crossrefs

Programs

  • Mathematica
    Count[Flatten[IntegerPartitions[#]],FactorInteger[#][[1,1]]]&/@ Select[ Range[ 60],CompositeQ] (* Harvey P. Dale, Sep 08 2018 *)