-106

Appears in sequences

• Expansion of Product_{m >= 1} (1 + q^m)^(-2).at n=21A022597
• Expansion of Product_{m>=1} (1 - m*q^m)^8.at n=4A022668
• First differences of sigma(n).at n=59A053222
• Second differences of sigma(n).at n=40A053223
• Coefficients of the '10th-order' mock theta function X(q).at n=67A053283
• McKay-Thompson series of class 30G for the Monster group.at n=29A058618
• a(n) = 2*n*mu(n).at n=52A062004
• A measure of how close the golden ratio is to rational numbers.at n=50A066212
• a(n) = -Sum_{d|n} (-n/d)^d.at n=11A076717
• a(n) = sigma(n) - 4*phi(n).at n=36A079546
• a(n) = prime(n) + prime(n-1) - a(n-1), with a(0)=0, a(1)=127, and prime(i) is the i-th prime.at n=8A082456
• Riordan array (((1+x)^2 - x^3)/(1+x)^3, 1/(1+x)).at n=47A099569
• Triangular matrix T, read by rows, that satisfies: [T^-k](n,k) = -T(n,k-1) for n >= k > 0, or, equivalently, (column k of T^-k) = -SHIFT_LEFT(column k-1 of T) when zeros above the diagonal are ignored. Also, matrix inverse of triangle A107876.at n=22A107889
• Expansion of q^(-1) * f(-q^2, -q^5)^2 * f(-q^3, -q^4) / f(-q^1, -q^6)^3 in powers of q where f() is Ramanujan's two-variable theta function.at n=28A108481
• Expansion of q^(-1) * f(-q^2, -q^5)^2 * f(-q^3, -q^4) / f(-q^1, -q^6)^3 in powers of q where f() is Ramanujan's two-variable theta function.at n=19A108481
• Difference between n and the sum of the factorials of its digits.at n=14A108911
• Row sums of number triangle A112334.at n=36A112335
• Expansion of g.f. 1/(1 - x + 2*x^3 + x^4).at n=12A112518
• Sum(mu(i)*phi(j): i+j=n), with mu=A008683 and phi=A000010.at n=35A112962
• Inverse of a Delannoy related triangle.at n=24A113141