22161

Appears in sequences

• Numbers having four 3's in base 9.at n=21A043468
• Numbers whose base-3 representation has exactly 10 runs.at n=6A043590
• Numbers n such that number of runs in the base 3 representation of n is congruent to 1 mod 9.at n=24A043807
• Numbers n such that number of runs in the base 3 representation of n is congruent to 0 mod 10.at n=6A043815
• First element of first run of exactly n consecutive numbers not of form x^2+y^2.at n=16A104271
• Numbers that cannot be expressed as a sum of 2 triangular numbers and a power of 2.at n=2A112665
• a(n) = (4*n + 3)*(1 + 2*n^2)/3.at n=20A168574
• Number of 4-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero and first differences in -n..n.at n=39A208995
• Number of partitions p of n including floor(mean(p)) as a part.at n=40A241334
• Triangle read by rows: row n gives coefficients of Schur polynomial Omega(n) in order of decreasing powers of x.at n=76A269750
• Expansion of Product_{k>=1} (1 + x^(k*(k+1)/2))^(k*(k+1)/2).at n=40A298850
• Odd numbers k > 1 such that k == 1 (mod 4), Product_{n>=1} (a(n)-1)/(a(n)+1) = Pi/4, and Limit_{n->oo} a(n+1)/a(n) = 3, where a(1) = 13 (see comments).at n=7A317986
• Numbers k such that (Sum of totatives of k) == 1 (mod Sum of primes dividing k with multiplicity).at n=43A340299