28390

Appears in sequences

• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 501", based on the 5-celled von Neumann neighborhood.at n=34A272566
• Composite numbers k such that 2^(k-1) == - lambda(k) (mod k), where lambda is the Carmichael lambda function (A002322).at n=7A330446
• Largest number whose base-n expansion cannot be subdivided to form a sequence of numbers which ordered form a multiple of n+1 when using +, *, and ().at n=11A330671
• Triangle read by rows: Take a pentagram with all diagonals drawn, as in A331906. Then T(n,k) = number of k-sided polygons in that figure for k = 3, 4, ..., n+2.at n=19A331907
• Starts of runs of 3 consecutive integers that are Stolarsky-Niven numbers (A364123).at n=5A364125