21878

Appears in sequences

• McKay-Thompson series of class 17A for the Monster simple group.at n=20A058530
• Triangle T(n,k) (0 <= k <= n) read by rows: top entry is 1, all other rows begin with 0; typical entry is sum of entry to left plus sum of all entries above it in the triangle.at n=35A059226
• Last entry in n-th row of triangle defined in A059226.at n=7A059227
• a(n) = Frobenius number for 3 successive primes = F[p(n), p(n+1), p(n+2)].at n=45A138989
• McKay-Thompson series of class 17A for the Monster group with a(0) = 2.at n=20A152944
• Semiprimes sp such that sp plus its digit sum is a perfect square.at n=24A244733
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 590", based on the 5-celled von Neumann neighborhood.at n=41A273117
• Unitary untouchable numbers with a record gap to the next unitary untouchable number.at n=5A306748
• Number of compositions with alternating parts weakly decreasing (or weakly increasing).at n=25A342528
• Number of integer partitions of n with the same number of adjacent equal parts as adjacent unequal parts.at n=52A385574