43785

Appears in sequences

• 10-gonal numbers for which the sum of the digits is also a 10-gonal number.at n=15A119547
• Near-prime numbers: numbers n such that n-2=prime, n+2=prime, n-4=prime, n+4=prime, n-8=prime, n+8=prime.at n=4A143727
• Number of binary strings of length n with no substrings equal to 0001, 1000 or 1001.at n=17A164485
• Numbers k such that k-4, k-2, k+2 and k+4 are prime.at n=24A173037
• Number of lower triangles of an n X n 0..4 array with new values introduced in row major order 0..4 and no element equal to more than one horizontal or vertical neighbor.at n=3A194536
• T(n,k) is the number of lower triangles of an n X n 0..k array with new values introduced in row major order 0..k and no element equal to more than one horizontal or vertical neighbor.at n=24A194540
• Odd numbers n such that 2n/sigma(n) - 1 = 1/x for some positive integer x.at n=22A222263
• Odd numbers k that are closer to being perfect than previous terms and also satisfy the condition that gcd(k, A003961(k)) is equal to gcd(sigma(k), A003961(k)), where A003961(n) is fully multiplicative with a(prime(k)) = prime(k+1), and sigma is the sum of divisors function.at n=10A386421