A290240 The number of unitary untouchable numbers <= 10^n.
5, 5, 9, 75, 862, 9903, 101030, 1028263
Offset: 1
Links
- Carl Pomerance and Hee-Sung Yang, Variant of a theorem of Erdős on the sum-of-proper-divisors function, Mathematics of Computation, Vol. 83, No. 288 (2014), pp. 1903-1913.
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