31456

Appears in sequences

• Numbers k such that sigma(k) = 2*phi(k+1).at n=20A068423
• a(n) is the smallest number greater than a(n-1) such that in a(0) through a(n) no digit occurs more than once more than any other digit.at n=35A095204
• Number of permutations of length n without increasing or decreasing modular 3-sequences.at n=5A165963
• Numbers k for which there are no prime numbers in the range (k-4*sqrt(sqrt(k)), k].at n=20A192320
• a(n) is the smallest number greater than a(n-1) such that in a(1) through a(n) no digit occurs more than once more than any other digit, starting with a(1) = 1.at n=35A248651
• Number of (n+1) X (1+1) 0..2 arrays with no 2 X 2 subblock having its maximum diagonal element less than the absolute difference of its antidiagonal elements.at n=3A251003
• Number of (n+1)X(4+1) 0..2 arrays with no 2X2 subblock having its maximum diagonal element less than the absolute difference of its antidiagonal elements.at n=0A251006
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with no 2X2 subblock having its maximum diagonal element less than the absolute difference of its antidiagonal elements.at n=6A251010
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with no 2X2 subblock having its maximum diagonal element less than the absolute difference of its antidiagonal elements.at n=9A251010
• Number of maximal independent vertex sets (and minimal vertex covers) in the n X n black bishop graph.at n=9A290594
• Number of maximal independent vertex sets (and minimal vertex covers) in the n X n white bishop graph.at n=8A290613
• "Erase or triple": list of the successive integers that produce the next "altitude" record (see the comments section).at n=13A300150
• Number of nX4 0..1 arrays with every element unequal to 1, 2, 4, 6, 7 or 8 king-move adjacent elements, with upper left element zero.at n=12A316753
• T(n, m) = Sum_{k=1..(m+3)/2} C(m-k+2, k-1)*C(n+1, k-1)*C(n-m+k-1, k-1)*C(2*n-2*k+4, 2*m-4*k+5)/(C(2*k-2, k-1)*C(2*m-2*k+4, 2*k-2))/2, triangle read by rows.at n=40A338372
• Triangle read by rows: T(n,k) is the number of permutations of k elements from [1..n] with longest consecutive chain size less than 3, when 1 and n are considered to be consecutive.at n=44A340107
• Number of integer partitions of n of odd rank.at n=43A340692