20271

Appears in sequences

• Numbers k such that 95*2^k+1 is prime.at n=30A032397
• First minimum value > 0 of the form x^3-k^2 when k > n^3.at n=26A070959
• Number of n-digit numbers that are divisible by a square and have the same property if any number of rightmost digits is deleted.at n=6A237608
• Number of cyclic compositions (necklaces of positive integers) summing to n that have only one part or whose consecutive parts (including the last with first) are indivisible.at n=34A318729
• Number T(n,k) of partitions of [n] having exactly k parity changes within the partition, n>=0, 0<=k<=max(0,n-1), read by rows.at n=65A363519
• Expansion of (1/x) * Series_Reversion( x * (1-x) / (1+x^2)^2 ).at n=8A369226
• Odd numbers m for which A379113(m^2) > 1, i.e., k = m^2 has a proper unitary divisor d > 1 such that A048720(A065621(sigma(d)),sigma(k/d)) is equal to sigma(k).at n=39A379122