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Perfect Number -- from Wolfram MathWorld

Perfect numbers are positive integers n such that n=s(n), (1) where s(n) is the restricted divisor function (i.e., the sum of proper divisors of n), or equivalently sigma(n)=2n, (2) where sigma(n) is the divisor function (i.e., the sum of divisors of n including n itself). For example, the first few perfect numbers are 6, 28, 496, 8128, ... (OEIS A000396), since 6 = 1+2+3 (3) 28 = 1+2+4+7+14 (4) 496 = 1+2+4+8+16+31+62+124+248, (5) etc. The nth perfect number is implemented in the...



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Perfect Number -- from Wolfram MathWorld

https://mathworld.wolfram.com/PerfectNumber.html

Perfect numbers are positive integers n such that n=s(n), (1) where s(n) is the restricted divisor function (i.e., the sum of proper divisors of n), or equivalently sigma(n)=2n, (2) where sigma(n) is the divisor function (i.e., the sum of divisors of n including n itself). For example, the first few perfect numbers are 6, 28, 496, 8128, ... (OEIS A000396), since 6 = 1+2+3 (3) 28 = 1+2+4+7+14 (4) 496 = 1+2+4+8+16+31+62+124+248, (5) etc. The nth perfect number is implemented in the...



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https://mathworld.wolfram.com/PerfectNumber.html

Perfect Number -- from Wolfram MathWorld

Perfect numbers are positive integers n such that n=s(n), (1) where s(n) is the restricted divisor function (i.e., the sum of proper divisors of n), or equivalently sigma(n)=2n, (2) where sigma(n) is the divisor function (i.e., the sum of divisors of n including n itself). For example, the first few perfect numbers are 6, 28, 496, 8128, ... (OEIS A000396), since 6 = 1+2+3 (3) 28 = 1+2+4+7+14 (4) 496 = 1+2+4+8+16+31+62+124+248, (5) etc. The nth perfect number is implemented in the...

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      Perfect Number -- from Wolfram MathWorld
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      Perfect numbers are positive integers n such that n=s(n), (1) where s(n) is the restricted divisor function (i.e., the sum of proper divisors of n), or equivalently sigma(n)=2n, (2) where sigma(n) is the divisor function (i.e., the sum of divisors of n including n itself). For example, the first few perfect numbers are 6, 28, 496, 8128, ... (OEIS A000396), since 6 = 1+2+3 (3) 28 = 1+2+4+7+14 (4) 496 = 1+2+4+8+16+31+62+124+248, (5) etc. The nth perfect number is implemented in the...
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      Perfect numbers are positive integers n such that n=s(n), (1) where s(n) is the restricted divisor function (i.e., the sum of proper divisors of n), or equivalently sigma(n)=2n, (2) where sigma(n) is the divisor function (i.e., the sum of divisors of n including n itself). For example, the first few perfect numbers are 6, 28, 496, 8128, ... (OEIS A000396), since 6 = 1+2+3 (3) 28 = 1+2+4+7+14 (4) 496 = 1+2+4+8+16+31+62+124+248, (5) etc. The nth perfect number is implemented in the...

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      Perfect Number -- from Wolfram MathWorld
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      Perfect numbers are positive integers n such that n=s(n), (1) where s(n) is the restricted divisor function (i.e., the sum of proper divisors of n), or equivalently sigma(n)=2n, (2) where sigma(n) is the divisor function (i.e., the sum of divisors of n including n itself). For example, the first few perfect numbers are 6, 28, 496, 8128, ... (OEIS A000396), since 6 = 1+2+3 (3) 28 = 1+2+4+7+14 (4) 496 = 1+2+4+8+16+31+62+124+248, (5) etc. The nth perfect number is implemented in the...

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      Perfect Number -- from Wolfram MathWorld
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      Perfect numbers are positive integers n such that n=s(n), (1) where s(n) is the restricted divisor function (i.e., the sum of proper divisors of n), or equivalently sigma(n)=2n, (2) where sigma(n) is the divisor function (i.e., the sum of divisors of n including n itself). For example, the first few perfect numbers are 6, 28, 496, 8128, ... (OEIS A000396), since 6 = 1+2+3 (3) 28 = 1+2+4+7+14 (4) 496 = 1+2+4+8+16+31+62+124+248, (5) etc. The nth perfect number is implemented in the...
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