30005

Appears in sequences

• Number of partitions of n into parts not of the form 17k, 17k+7 or 17k-7. Also number of partitions with at most 6 parts of size 1 and differences between parts at distance 7 are greater than 1.at n=41A035968
• Numbers n such that there are (presumably) nine palindromes in the Reverse and Add! trajectory of n.at n=9A090070
• Given the infinite continued fraction i+(i/(i+(i/(i+...)))), where i is the square root of (-1), this is the denominator of the real part of the convergents.at n=15A091807
• Given the infinite continued fraction i+(i/(i+(i/(i+...)))), where i is the square root of (-1), this is the denominator of the imaginary part of the convergents.at n=15A091809
• a(n) = |b(n)|^2 = x^2 + 3*y^2 where (x,y,y,y) is the quaternion b(n) of the sequence b of quaternions defined by b(0)=1,b(1)=1, b(n) = b(n-1) + b(n-2)*(0,c,c,c) where c = 1/sqrt(3).at n=15A105309
• Numbers k such that k and k^2 use only the digits 0, 2, 3, 5 and 9.at n=42A136891
• 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, 1), (0, 1, -1), (1, -1, 0), (1, 1, 1)}.at n=8A149776
• a(n) = 1681*n^2 - 2606*n + 1010.at n=4A157110
• Composite numbers whose sum of aliquot parts divides the sum of their unrelated numbers.at n=9A250399