23804

Appears in sequences

• Number of solutions to c(1)*prime(3)+...+c(n)*prime(n+2) = 2, where c(i) = +-1 for i>1, c(1) = 1.at n=23A022902
• a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 3, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1 and a(2) = 3.at n=16A049924
• Numbers k such that k divides the (k+1)st Lucas number.at n=8A094397
• Planar trees where no branch is identical to its adjacent neighbor.at n=15A106363
• a(n) = 4*(5*n^2 - 5*n + 1).at n=34A193448
• Total sum of odd parts in the last section of the set of partitions of n.at n=30A206435
• Number of partitions p of n such that (number of numbers of the form 5k in p) is a part of p.at n=42A241549
• Even composite integers m such that U(m)^2 == 1 (mod m) and V(m) == 3 (mod m), where U(m)=A001906(m) and V(m)=A005248(m) are the m-th generalized Lucas and Pell-Lucas numbers of parameters a=3 and b=1, respectively.at n=10A337777
• Even composite integers m such that U(m)^2 == 1 (mod m) and V(m) == 7 (mod m), where U(m)=A004187(m) and V(m)=A056854(m) are the m-th generalized Lucas and Pell-Lucas numbers of parameters a=7 and b=1, respectively.at n=38A337782