92541

Appears in sequences

• Consider a triangle in which the 2n-th row contains first 2n positive integers in increasing order and the (2n+1)-st row contains first 2n+1 positive integers in decreasing order; sequence contains concatenation of numbers read upward at a 45-degree angle.at n=8A079809
• a(n) = Sum_{r>0,s>0} binomial(r*s-1,n-1)/2^(r+s).at n=6A123114
• a(n) is the smallest number which is the sum of two positive n-gonal numbers in more than one way.at n=29A199809