79750

Appears in sequences

• Smaller of an amicable pair: (a,b) such that sigma(a) = sigma(b) = a+b, a < b.at n=12A002025
• Amicable numbers.at n=23A063990
• Riordan array (1/(1-xc(2x)),xc(2x)/(1-xc(2x))), c(x) the g.f. of A000108.at n=38A110506
• Riordan array (1/(1+xc(-2x)), xc(-2x)/(1+xc(-2x))), c(x) the g.f. of A000108.at n=38A114189
• Smaller member of an infinitary amicable pair.at n=19A126169
• Infinitary amicable numbers.at n=34A127664
• Conjectured list of smallest terms of k-sociable cycles of order r.at n=22A183016
• Conjectured list of multisociable numbers.at n=36A183019
• Numbers k such that sigma(k) = sigma(sigma(k)-k).at n=27A206708
• Abundant numbers whose aliquot sequence is abundant, deficient, abundant, ..., etc.at n=14A234969
• Number of (3+1) X (n+1) 0..1 arrays with every 2 X 2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically.at n=38A258556
• Amicable pairs.at n=24A259180
• Amicable pairs (x < y) ordered by nondecreasing sum (x + y) and then by increasing x.at n=24A259933
• Smaller of amicable pair (x, y) as they are listed in A259933.at n=12A260086
• Amicable pairs of even numbers.at n=18A262622
• Even amicable numbers.at n=18A262624
• List of pairs of amicable numbers (m,n) where the sum of the pair is divisible by 10.at n=10A291422
• Smaller of bi-unitary amicable pair.at n=21A292980
• Lesser of tri-unitary amicable numbers pair: numbers (m, n) such that tsigma(m) = tsigma(n) = m + n, where tsigma(n) is the sum of the tri-unitary divisors of n (A324706).at n=15A324708
• Amicable pairs with the property that the number of divisors of the smaller member is greater than the number of divisors of the larger member.at n=12A328063