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- #!/usr/bin/ruby
- # Perfect powers that are equal to the sum of the first k perfect powers > 1 for some k.
- # https://oeis.org/A364948
- # Known terms:
- # 4, 121, 2548735225
- # Next term, if it exists, is > 979846576384.
- var sum = 0
- var sums = Set()
- var n = 1
- for k in (2..1e9) {
- n = n.next_perfect_power
- sum += n
- sums << sum
- if (sums.has(n)) {
- say [n, k]
- }
- }
- __END__
- [4, 2]
- [121, 14]
- [2548735225, 51912]
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