335872

Appears in sequences

• Expansion of (theta_3(q) / theta_4(q) )^4 in powers of q; also of 1 / (1 - lambda(z)).at n=8A014972
• Expansion of phi(q^4) / phi(q) in powers of q where phi() is a Ramanujan theta function.at n=32A112128
• Expansion of (theta_4(q) / theta_3(q))^4 in powers of q.at n=8A128692
• Expansion of (phi(q^2) / phi(-q))^2 in powers of q where phi() is a Ramanujan theta function.at n=16A131126
• Expansion of -lambda(t + 1) in powers of the nome q = exp(Pi i t).at n=7A132136
• Expansion of phi(q^4) / phi(-q) in powers of q where phi() is a Ramanujan theta function.at n=32A208933
• Expansion of (phi(q^2) / phi(q))^2 in powers of q where phi() is a Ramanujan theta function.at n=16A210066
• Expansion of q * phi(q) * psi(q^8) / (phi(-q) * phi(q^4)) in powers of q where phi(), psi() are Ramanujan theta functions.at n=31A215348
• a(n) = prime(n) * 2^n.at n=12A265127
• a(0) = 0, a(n) = Sum_{0<d|n, n/d odd} d^4 for n > 0.at n=24A285989
• a(n) = [x^n] Product_{k>=0} ((1 + x^(2*k+1))/(1 - x^(2*k+1)))^n.at n=8A291697
• Numbers with prime factorization Product_{k=1..w} prime(i_k) ^ e_k (where w = A001221(n) and prime(i) denotes the i-th prime number) such that i_k <> e_k for k = 1..w and { i_1, ..., i_w } = { e_1, ..., e_w }.at n=37A320252
• Numbers whose ordered prime signature is equal to the set of distinct prime indices in decreasing order.at n=36A324571
• Numbers k such that the smallest m such that k | psi(m) is even, psi = A002322.at n=30A341886
• Sum of the 4th powers of the divisor complements of the odd proper divisors of n.at n=23A352050
• Numbers whose product of prime indices equals their product of prime exponents (prime signature).at n=28A353503
• a(n) is the number of exterior top arches (no covering arch) for semi-meanders in generation n+1 that are generated by semi-meanders with n top arches and floor((n+2)/2) exterior top arches using the exterior arch splitting algorithm.at n=25A365679