234900

Appears in sequences

• Icosagonal numbers divisible by 20.at n=33A117798
• Expansion of 1/(1 - x^2 - 2 x^3 + x^4).at n=40A122512
• Define an array by d(m, 0) = 1, d(m, 1) = m; d(m, k) = (m - k + 1) d(m+1, k-1) - (k-1) (m+1) d(m+2, k-2). Sequence gives d(n,4).at n=24A126958
• a(n) = 378*n^2 - 54*n (n>=1).at n=24A305070
• Numbers k such that for some r we have phi(1) + ... + phi(k - 1) = phi(k + 1) + ... + phi(k + r), where phi(i) = A000010(i).at n=19A358936
• Exponential abundant numbers that are not exponential unitary abundant.at n=32A391085