12058624

Appears in sequences

• Denominators of Taylor series expansion of arcsin(x). Also arises from arccos(x), arccsc(x), arcsec(x), arcsinh(x).at n=11A002595
• 20-almost primes (generalization of semiprimes).at n=23A069281
• a(n) = n*2^(n-4).at n=19A079859
• a(0) = a(1) = 1; for n > 1, a(n) = (n+2)*2^(n-2).at n=21A087447
• First differences of A129952.at n=21A129953
• Numbers that are not the sum of two squares and two fourth powers.at n=35A214891
• Expansion of x*(5+x+x^2)/(1-2*x).at n=22A248646
• Let S_k denote the sequence of numbers j such that A001222(j) - A001221(j) = k. Then a(n) is the n-th term of S_n.at n=17A261256
• a(n) = the number of hills (arch length of 1 with no covering arches) for semi-meander solutions with n arches and floor((n+2)/2) arch group returns to the x axis.at n=41A262258
• Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 217", based on the 5-celled von Neumann neighborhood.at n=26A286741