20329

Appears in sequences

• Number of atoms in a decahedron with n shells.at n=29A004068
• Strong pseudoprimes to base 44.at n=17A020270
• Strong pseudoprimes to base 56.at n=14A020282
• Numbers k such that phi(k) and cototient(k) are squares but k is not in A054755.at n=14A054756
• Numbers k such that reverse(gpf(k)) = gpf(k+1), where gpf(n) = A006530(n); a(1)=1.at n=28A071844
• Column 11 of array illustrated in A089574 and related to A034261.at n=3A109821
• Column 11 of table A105552.at n=10A110554
• Odd numbers n for which 17 is the smallest i (>= 1) with Jacobi symbol J(i,n) getting either a value 0 or -1.at n=24A112077
• a(n) = 25*a(n-2) + 48*a(n-3) with a(0) = 0, a(1) = a(2) = 1.at n=7A114553
• Numbers n such that f(n), f(n+1) and f(n+2) are prime, f(m)=72*m^2+7.at n=22A121089
• a(n) = 42*n^2 + 1.at n=22A158604
• Total sum of nonprime parts in all partitions of n.at n=24A194545
• L.g.f.: Sum_{n>=1} x^n/n * Product_{d|n} (1 + d*x^n)^d.at n=32A205483
• Number of (w,x,y,z) with all terms in {1,...,n} and |w-x|=|x-y|+|y-z|.at n=29A212570
• Fundamental discriminants d uniquely characterizing all complex biquadratic fields Q(sqrt(-3),sqrt(d)) which have 3-class group of type (3,3) and second 3-class group isomorphic to SmallGroup(729,95).at n=10A250239
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 33", based on the 5-celled von Neumann neighborhood.at n=32A269812
• Prime time numbers on 6-digit clocks: numbers of the form HMMSS where H, MM, SS are primes, H < 24, MM and SS < 60.at n=26A295014
• MM-numbers of crossing, capturing multiset partitions (with empty parts allowed).at n=5A326259
• Odd composite integers m such that A087130(m) == 5 (mod m).at n=34A335671