Those Fascinating Numbers 163
4 683
the sixth horse number (see the number 13).
4 713
the second number n 1 such that n · 2n + 1 is prime (see the number 141).
4 725 (=
33
·
52
· 7)
the seventh odd abundant number (see the number 945).
4 787
the 13th prime number pk such that p1p2 . . . pk + 1 is prime (see the number
379).
4 788
the
14th
Keith number (see the number 197).
4 793
the
29th
Lucas prime number (see the number 613).
4 801
the largest known prime number p such that P (p2 1) 7 and P (p2 1) = 7,
where P (n) stands for the largest prime factor of n.
4 802
the smallest number which can be written respectively as the sum of two and
of three fourth powers: 4 802 =
74 +74
=
34 +54 +84
(see the number 617 057).
4 850
the fifth composite number n such that σ(n + 6) = σ(n) + 6 (see the number
104).
4 862
the ninth Catalan number (see the number 14).
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