261156

Appears in sequences

• a(n) = 2^n - C(n,0) - C(n,1) - C(n,2) - C(n,3).at n=18A002663
• Sum_{k=0..14} binomial(n,k).at n=18A220051
• Numbers k such that k and k+2 are both unitary untouchable numbers (A063948).at n=21A357323
• Number of defective (binary) heaps on n elements from the set {0,1} where exactly one ancestor-successor pair does not have the correct order.at n=27A372643