27927

Appears in sequences

• phi(n) + phi(reverse(n)) = sigma(n).at n=8A071846
• L-th order palindromes with L > 2.at n=25A089381
• Expansion of x^2*(-3+4*x)/(1-x^3+x^4).at n=57A110061
• Expansion of q / (chi(-q) * chi(-q^11))^2 in powers of q where chi() is a Ramanujan theta function.at n=32A123631
• Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+409)^2 = y^2.at n=8A129641
• Numbers k such that k and k^2 use only the digits 1, 2, 3, 7 and 9.at n=20A136983
• 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, -1, 1), (-1, 0, 0), (0, 0, -1), (0, 1, 0), (1, 0, 0)}.at n=9A149919
• Decimal representation of the x-axis, from the origin to the right edge, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 590", based on the 5-celled von Neumann neighborhood.at n=14A283178
• a(1) = 1, for n >= 2 let the digits of a(n-1) be d_1, ..., d_i in base 10. Starting from d_1 do the following procedure: if d_r is divisible by 2, then d_r_new = d_r / 2, otherwise d_r_new = 3*d_r. a(n) = concatenation of d_r_new for r = 1 to i.at n=7A306681