19424

Appears in sequences

• Numbers k such that (k+3, k+5, k+17, k+257, k+65537) are all primes.at n=18A063799
• Solutions to A096509[x]=6; number of prime-powers [including primes] in the neighborhood of x with Ceiling[Log[x]] radius equals 6.at n=16A096517
• Expansion of (1+2*x)/((1+x)*(1-x^2-x^3)).at n=37A098601
• Sum of squares of pentanacci numbers (A001591).at n=12A107243
• Triangle T(n,k), read by rows, given by (1, 2, -2, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 2, -1, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938.at n=41A182412
• Number of ordered triples (w,x,y) with all terms in {-n,...-1,1,...,n} and w+2x+2y>0.at n=17A211624
• Number of (w,x,y,z) with all terms in {1,...,n} and 2*w*x>3*y*z.at n=15A211922
• Binomial transform of A215495(n).at n=12A217988
• Number of 2 X 2 matrices having entries in {0,1,...,n} and determinant in the open interval (-n,n) with no entry repeated.at n=20A279273
• Number of permutations on [n+3] with no circular 3-successions.at n=4A284844
• Numbers k such that k!6 - 9 is prime, where k!6 is the sextuple factorial number (A085158).at n=23A289687
• Expansion of Product_{k>=1} (1 + x^k) * (1 + x^(2*k)) * (1 + x^(3*k)) * (1 + x^(4*k)) / ((1 - x^k) * (1 - x^(2*k)) * (1 - x^(3*k)) * (1 - x^(4*k))).at n=15A327049
• Number of 9-regular cubic partitions of n.at n=27A335604
• Number of plane partitions of n having exactly one row and one column, each of equal length.at n=29A356367
• G.f. satisfies A(x) = 1 + 2*x*A(x) + 2*x^3*A(x)^3.at n=9A367113
• Number of non-unitary square divisors of n!.at n=36A375188
• Number of non-unitary square divisors of n!.at n=37A375188
• Number of fixed polyaboloes (or polytans) with n cells, where two triangles sharing a hypotenuse (making up a square) are counted as a single cell.at n=5A390998