83977

Appears in sequences

• a(n) = 6*binomial(n,4) + 3*binomial(n,3) + 4*binomial(n,2) - n + 2.at n=24A066375
• Numerator of Sum_{k=1..n} phi(k)/k.at n=12A071708
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (0, 1, -1), (1, 0, -1), (1, 1, -1), (1, 1, 1)}.at n=9A149642
• Number of binary strings of length n with no substrings equal to 0000 0110 or 1011.at n=17A164440
• a(n) is the numerator of the density of natural numbers m such that gcd(m,floor(m/n))=1.at n=13A250031