21633

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 98.at n=29A031596
• Number of conjugacy classes in the symmetric group S_n that have even number of elements.at n=36A060643
• a(n) = 676*n + 1.at n=31A158386
• G.f.: A(x) = exp( Sum_{n>=1} sigma(n)*x^n/(1+x^n) /n ).at n=51A158441
• a(n) = 32*n^2 + 1.at n=26A158575
• Numbers n with property that average digit of n^2 is s=7.at n=18A164773
• First lower diagonal of Parker's triangle A047812.at n=34A335323
• a(n) = number of terms in row n of the array A378282.at n=28A378286