90271

Properties

Appears in sequences

• Sort then Add, a(1)=17.at n=15A033899
• Smallest number k for which k, 2k, ... nk all contain the digit 1.at n=14A039932
• Smallest number k for which k, 2k, ... nk all contain the digit 1.at n=15A039932
• Smallest number k for which k, 2k, ... nk all contain the digit 1.at n=16A039932
• Smallest number k for which k, 2k, ... nk all contain the digit 1.at n=17A039932
• Smallest number k for which k, 2k, ... nk all contain the digit 1.at n=18A039932
• Smallest number k for which k, 2k, ... nk all contain the digit 1.at n=19A039932
• Smallest number k for which k, 2k, ... nk all contain the digit 1.at n=20A039932
• Smallest number k for which k, 2k, ... nk all contain the digit 1.at n=21A039932
• Successive record-setters for tau(n+1)*tau(n-1)/tau(n)^2, where tau(n) is the number of divisors of n.at n=26A094342
• Primes p such that continued fraction of (1 + sqrt(p))/2 has period 16 : primes in A146339.at n=33A146361
• Least number k such that d(k-1) = d(k+1) = 2n or 0 if no such k exists, where d(n)=A000005(n).at n=23A190646
• Prime numbers p where d(p-1) = d(p+1) increases to a record.at n=8A190821
• E.g.f. satisfies: A(x) = Sum_{n>=0} x^n/n! * ( d/dx x*A(x)^n ) / A(x)^n.at n=6A245308
• Record values in A039932.at n=5A319542
• Primes p such that min(d(p-1), d(p+1)) is larger than the corresponding values of all previous primes, where d(n) is the number of divisors of n (A000005).at n=17A319823
• Primes p such that d(p^2-1) sets a record, where d(n) is the number of divisors of n.at n=28A335325
• a(n) is the smallest number m such that tau(m-1) = tau(m+1) = n*tau(m) or 0 if no such m exists, where tau(k) = A000005(k).at n=23A350935
• Expansion of 1/((1-x)^8 - 16*x^8)^(1/8).at n=18A376836
• Prime numbersat n=8743