52012

Appears in sequences

• Number of unsensed planar maps with n edges and without faces or vertices of degree 1.at n=11A006397
• a(n) = T(n,[ n/2 ] - 1), where T is the array in A026120.at n=15A026133
• Base 4 digits are, in order, the first n terms of the periodic sequence with initial period 3,0,2.at n=7A037653
• Number of perfect rulers with n segments (n>=0).at n=13A103301
• Number of nX4 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.at n=6A300535
• Number of n X 7 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.at n=3A300538
• T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.at n=48A300539
• T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.at n=51A300539
• a(0)=0, a(1)=1; for n>1, a(n) = a(n-1)+a(n-2), except where a(n-1) is a prime greater than 2, in which case a(n) = a(n-1)-a(n-2).at n=39A376930
• a(0)=0, a(1)=1; for n>1, a(n) = a(n-1)+a(n-2), except where a(n-1) is a prime greater than 2, in which case a(n) = a(n-1)-a(n-2).at n=42A376930
• The number of n-free abundant numbers below the least number k that is not n-free whose sum of n-free divisors is larger than 2*k.at n=1A387155