91072

Appears in sequences

• a(n) = ( 1/1 + 1/3 + 1/5 + ... + 1/(2*n-1) )*LCM(1, 3, 5, ..., 2*n-1).at n=7A025550
• Numerators of alternating sum transform (PSumSIGN) of Harmonic numbers H(n) = A001008/A002805.at n=14A035048
• Numerator of Sum_{1<=k<=n, gcd(k,n)=1} 1/k.at n=15A093600
• a(n) = numerator of the sum of reciprocals of the terms in n-th row of triangle A077581.at n=7A126577
• 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, 0, 0), (0, -1, 0), (1, 1, 0), (1, 1, 1)}.at n=9A150714
• Number of permutations of 2 copies of 1..n avoiding adjacent step pattern up, down.at n=5A177554
• Numerators of Sum_{j=0..n} 1/(2*j+1), for n >= 0.at n=7A350669
• T(j,k) are the numerators u in the representation R = s/t + (2/Pi)*u/v of the resistance between two nodes separated by the distance vector (j,k) in an infinite square lattice of one-ohm resistors, where T(j,k), j >= 0, 0 <= k <= j, is a triangle read by rows.at n=44A355566