30457

Appears in sequences

• Numbers k such that sopf(k) + 1 = sopf(k+1), where sopf(k) = A008472(k).at n=25A064111
• Total number of brown nodes among tricolored labeled trees on n nodes.at n=4A097172
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 1), (0, 0, -1), (0, 1, 1), (1, -1, -1)}.at n=10A148618
• Numbers k such that 6*prime(k) -+ {1,5} are all prime.at n=39A174393
• Sum of prime divisors of n (with repetition) is one less than the sum of prime divisors (with repetition) of n+1.at n=29A228126
• Numbers n such that (i) the sum of prime divisors of n (with repetition) is one less than the sum of prime divisors (with repetition) of n+1, and (ii) n and n+1 have the same number of prime divisors (with repetition).at n=11A237929
• Number of nX5 0..1 arrays with every element unequal to 1, 2, 4, 5 or 7 king-move adjacent elements, with upper left element zero.at n=6A305012
• Number of nX7 0..1 arrays with every element unequal to 1, 2, 4, 5 or 7 king-move adjacent elements, with upper left element zero.at n=4A305014
• T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 4, 5 or 7 king-move adjacent elements, with upper left element zero.at n=59A305015
• Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where A(n,k) is Sum_{j=0..floor(n/2)} ((n-j)!/j!)*binomial(n-j,j)*k^(n-2*j)*(-1)^j.at n=59A305466
• Numbers k such that A008475(k)+1 = A008475(k+1).at n=36A333801
• Numbers k such that A181894(k)+1 = A181894(k+1).at n=30A333802
• Numbers that can be represented in more than one way as p^2+p*q+q^2 with p and q primes, p<=q.at n=25A349987
• Numbers k such that (2^k-1)^k == 1 (mod (2^k+1)*k^2) and 2^(k-1) != 1 (mod k).at n=0A384148