261261

Appears in sequences

• 5-dimensional pyramidal numbers: a(n) = n*(n+1)*(n+2)*(n+3)*(2n+3)/5!.at n=25A005585
• a(n) = Sum_{i=1..floor((n+1)/4)} a(2*i-1) * a(n-2*i+1), with a(1)=3 and a(2)=a(3)=1.at n=13A024737
• Odd abundant numbers not divisible by 5.at n=7A064001
• Sixth column (m=5) of (1,6)-Pascal triangle A096956.at n=25A096959
• Integers are written in the form abcd...n where "a" means "At position a in this integer there is a digit b"; "b" means: "at position b there is a digit c"; "c" means: "at position c there is a digit d"; ... and "n" means: "at position n there is a digit a".at n=31A105956
• Odd admirable numbers: such that sigma(n) = 2n + 2d for some d | n.at n=21A109729
• Number of n X 6 binary arrays without the pattern 0 1 diagonally or vertically.at n=15A188840
• a(n) is the least integer that can be expressed as the difference of two heptagonal numbers in exactly n ways.at n=10A334036
• Admirable numbers with more divisors than any smaller admirable number.at n=9A364726
• Expansion of 1/(1 - 2*x - 3*x^2)^(7/2).at n=8A374506
• Expansion of Sum_{1<=i<=j<=k} q^(i+j+k)/( (1-q^i)*(1-q^j)*(1-q^k) )^2.at n=25A374930
• Odd abundant numbers that are also doublets (cf. A020338).at n=11A380232
• Odd abundant numbers not divisible by 5 that are also doublets (cf. A020338).at n=5A380233