42818

Appears in sequences

• Numbers k such that k and k+1 have same sum of divisors.at n=16A002961
• Numbers k such that k and k+1 have the same number and sum of divisors.at n=5A054004
• Numbers k such that sigma(k) divides sigma(k+1), where sigma(k) is sum of positive divisors of k.at n=29A058072
• Numbers k such that sigma(k+1) divides sigma(k), where sigma(k) is the sum of positive divisors of k.at n=36A058073
• Numbers k such that sigma(k)*omega(k) = sigma(k+1)*omega(k+1), where omega(k) is the number of distinct prime divisors of n (A001221).at n=11A063071
• Numbers k such that k and k+1 have the same sum of squarefree divisors, or sqf(k) = sqf(k+1), where sqf(k) = A048250(k).at n=15A063964
• Numbers k such that k and k+1 have the same sum of unitary divisors and the same number of divisors.at n=9A064348
• Numbers k such that k and k+1 have the same sum of unitary and nonunitary divisors.at n=7A064729
• Numbers k such that A065608(k) = A065608(k+1).at n=8A065062
• Numbers k such that k and k^2 use only the digits 1, 2, 3, 4 and 8.at n=33A136971
• Numbers k such that sigmawt(k) = sigmawt(k+1), where sigmawt(k) is the sum of the divisors of k weighted by divisor multiplicity in k.at n=8A171183
• Number of subwords of type uh^ju and dh^jd (j>=1), where u=(1,1), h=(1,0), and d=(1,-1), in all peakless Motzkin paths of length n (can be easily expressed using RNA secondary structure terminology).at n=15A190161
• Number of (n+1) X (n+1) -5..5 symmetric matrices with every 2 X 2 subblock having sum zero and three distinct values.at n=11A211330
• Numbers n such that sigma(n+1) - sigma(n) = k*n for some integer k, where sigma(n) = A000203 (sum of divisors of n).at n=24A223136
• Table of consecutive numbers with the same sum of divisors.at n=32A225757
• Runs of consecutive numbers with the same number and sum of divisors.at n=10A225758
• Numbers k such that the average of the divisors of k and k+1 is the same.at n=14A238380
• a(n) = (binomial(2n, n) - 2) mod n^3.at n=35A246133
• Numbers n such that Product_{d|n} sigma(d) = Product_{d|n+1} sigma(d).at n=5A280087
• Numbers k such that bsigma(k) = bsigma(k+1), where bsigma(k) is the sum of the bi-unitary divisors of k (A188999).at n=30A293183