21353

Appears in sequences

• sin(arcsinh(x)*exp(x)) = x+2/2!*x^2+1/3!*x^3-12/4!*x^4-75/5!*x^5...at n=8A012585
• Numbers k such that k^3 has only odd digits.at n=18A030099
• a(n) is smallest positive integer, distinct from any terms earlier in the sequence, such that (sum{k=1 to n}[a(k)]) divides (product{k=1 to n}[a(k)])*(sum{k=1 to n}[1/a(k)]).at n=8A058330
• Smallest multiple of (n+1)-st prime which is == 1 mod n-th prime.at n=36A073604
• "Fibonacci-digits": start with "11", append sum of first 2 digits to the preceding number, drop first digit.at n=11A093099
• a(n) = A100092(n^2+1).at n=14A100093
• Number of permutations of length n which avoid the patterns 1234, 1324, 3421.at n=11A116829
• Squarefree numbers (A005117) with prime factors in a prime(k) + k progression.at n=9A232169
• Squarefree numbers (A005117) of form prime(k)*q where q = primes of the form prime(k) + k.at n=8A232170
• Semiprimes whose prime factors are of equal binary length and which differ from each other in one bit position only.at n=22A261073
• Semiprimes whose prime factors differ from each other in one bit position only.at n=52A261077
• Maximum value of the cyclic convolution of first n primes with themselves.at n=18A299111