Euler problems/61 to 70
Find the sum of the only set of six 4-digit figurate numbers with a cyclic property.
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Find the smallest cube for which exactly five permutations of its digits are cube.
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How many n-digit positive integers exist which are also an nth power?
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How many continued fractions for N ≤ 10000 have an odd period?
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Find the sum of digits in the numerator of the 100th convergent of the continued fraction for e.
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Investigate the Diophantine equation x2 − Dy2 = 1.
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Using an efficient algorithm find the maximal sum in the triangle?
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What is the maximum 16-digit string for a "magic" 5-gon ring?
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Find the value of n ≤ 1,000,000 for which n/φ(n) is a maximum.
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10 Problem 70
Investigate values of n for which φ(n) is a permutation of n.
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