846. Magic Bracelets

A bracelet is made by connecting at least three numbered beads in a circle. Each bead can only display 1, 2, or any number of the form pk or 2pk for odd prime p.

In addition a magic bracelet must satisfy the following two conditions:

Define the potency of a magic bracelet to be the sum of numbers on its beads. The example is a magic bracelet with five beads which has a potency of 155.

Let F(N) be the sum of the potency of each magic bracelet which can be formed using positive integers not exceeding N, where rotations and reflections of an arrangement are considered equivalent. You are given F(20)=258 and F(102)=538768.

Find F(106).

846. 魔法数镯

一个数镯由至少三个标有数字的珠子和连接它们的环构成。数镯上的珠子的标号只能是 12pk2pk 四种形式之一(其中 p 为任意奇质数,k 为任意正整数)。

进一步,定义魔法数镯为满足以下条件的数镯:

对任意魔法数镯,定义其魔法效力为其所有珠子标号之和。上图中的魔法数镯共有 5 个珠子,魔法效力为 155。

F(N) 为:满足所有珠子标号均为不超过 N 的正整数的魔法数镯的魔法效力之和,其中,经旋转或翻转后相同的数镯视为相同的数镯。已知:F(20)=258F(102)=538768

F(106)


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