Those Fascinating Numbers 223
59 535
the second solution of γ(n + 1) γ(n) = 17 (see the number 1 681).
59 656
the eighth number n 1 such that n ·
2n
+ 1 is prime (see the number 141).
60 228
the seventh number n such that σ(n) and σ2(n) have the same prime factors,
namely the primes 2, 3, 5, 7 and 13 (see the number 180).
62 244
the fifth number n such that each of the numbers n + i, i = 0, 1, 2, . . . , 16, have
a factor in common with the other 16 (see the number 2 184).
62 471
(probably) the largest number which cannot be written as the sum of two co-
prime numbers whose index of composition is 1.8 (see the number 933).
64 210
the smallest number n such that

m≤n
σ(m) is a multiple of 100 000 (and of
1 000 000): here the sum is equal to 1 391 000 000.
64 540
the smallest number n such that π(n) = n/10 (see the number 330).
64 890
the second solution of σ(n) = 3n + 18 (see the number 17 850).
64 980
the eighth number n such that σ(n) and σ2(n) have the same prime factors,
namely the primes 2, 3, 7, 13 and 127 (see the number 180).
65 024
the fifth number n divisible by a square 1 and such that γ(n + 1) γ(n) = 1
(see the number 48).
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