49321

Appears in sequences

• Strong pseudoprimes to base 49.at n=21A020275
• Strong pseudoprimes to base 85.at n=24A020311
• Expansion of 1/(1-x^2-2*x^3).at n=28A052947
• q-factorial numbers 3!_q.at n=36A069778
• p(p^2-p+1) as p runs through the primes.at n=11A083558
• Expansion of (1-x)/((1-x)^2 - 4*x^3).at n=14A097117
• Expansion of g.f. (x^2+x+1)*(2*x^2+2*x+1)*(x-1)^2/((1-x^2-2*x^3)*(x^4+1)).at n=29A107850
• a(n) = Product of k primes in arithmetic progression with common difference 6, otherwise a(n) = prime(n).at n=8A120313
• Numbers n such that phi(n)=d_1!!*d_2!!*...*d_k!! where d_1 d_2 ... d_k is the decimal expansion of n.at n=25A139408
• Products of three consecutive primes of the form 6n+1 (see A002476).at n=3A154728
• a(n) = 36*n^2 + n.at n=36A157324
• a(n) = 1369*n^2 + 37.at n=6A158741
• Expansion of x^2/(1-x^2-2*x^3).at n=30A159287
• Diagonal sums of the Riordan array (1-4*x+4*x^2, x*(1-2*x)) (A167431).at n=24A167434
• a(n) = Sum_{d divides n} d*(n/d)^(d-1).at n=23A167531
• a(n) = abs(a(n-1) - 3*a(n-2)) with a(1)=a(2)=1.at n=24A192263
• Number of (n+2) X 5 0..1 matrices with each 3 X 3 subblock idempotent.at n=18A224554
• The number of permutations of length n sortable by 3 prefix reversals (in the pancake sorting sense).at n=37A228398
• S_13 sequence in partition of integers > 1 described in A240521.at n=14A241025
• Euler pseudoprimes to base 7: composite integers such that abs(7^((n - 1)/2)) == 1 mod n.at n=30A262054