16773120

Appears in sequences

• a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3), n > 3, with a(0)=a(1)=a(2)=0, a(3)=1.at n=26A000749
• Theta series of Leech lattice.at n=3A008408
• Number of Barlow packings with group P6(bar)m2 that repeat after 2n layers.at n=25A011949
• Expansion of g.f.: 2*x*(1-x)/((1-2*x)*(1-2*x^2)).at n=24A014236
• a(n) = 4^n - 2^n.at n=12A020522
• a(n) = 8^n - n^4.at n=8A024092
• Number of reversible strings with n beads of 2 colors. If more than 1 bead, not palindromic.at n=24A032085
• Second coefficient of extremal theta series of even unimodular lattice in dimension 24n.at n=1A034598
• Number of elements of GF(2^n) with trace 1 and subtrace 0.at n=26A038520
• Number of 2n-bead balanced binary necklaces which are equivalent to their reversed complement, but not equivalent to their reverse and complement.at n=25A045678
• Coefficients of J(0)*theta_3(z) where J(0) is sequence A056945.at n=12A056946
• Number of strings over Z_4 of length n with trace 0 and subtrace 2.at n=13A068774
• S(n; 0,3) = S(n; 2,1) where S(n; t,s) is the number of length n 4-ary strings whose digits sum to t mod 4 and whose sum of products of all pairs of digits sum to s mod 4.at n=13A068777
• Number of strings over Z_4 of length n with trace 2 and subtrace 2.at n=13A068790
• Number of words of length 2n in the two letters s and t that reduce to the identity 1 by using the relations ssTT=1, ststSS=1 and ststTT=1, where S and T are the inverses of s and t, respectively (i.e., sS=1 and tT=1). The generators s and t and the three stated relations generate the quaternion group Q4.at n=12A071930
• Number of strings of length n over GF(4) with trace 1 and subtrace x where x = RootOf(z^2+z+1).at n=13A073999
• Number of degree-n irreducible polynomials over GF(4) with trace 0 and subtrace 0.at n=15A074031
• Smallest oblong number having n prime divisors (with multiplicity).at n=16A083001
• Euler totient function phi values of multiperfect numbers.at n=12A098203
• Number of compositions of n with an odd number of 1's.at n=25A113980