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 A336354 Numbers k such that p^2 divides k, where p = A006530(k), the largest prime factor of k, and sigma(k) does not have any prime factor larger than p. 1
 343, 686, 1029, 1372, 1715, 2058, 2744, 3430, 4116, 4489, 5145, 6241, 6860, 8232, 8978, 9261, 10290, 10976, 12482, 13467, 13720, 17956, 18522, 18723, 18769, 20580, 22201, 22445, 24964, 26569, 26934, 31205, 31423, 32761, 32928, 35912, 36481, 37044, 37446, 37538, 40401 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 343 = 7^3 is present, as A000203(343) = 400 = 2^4 * 5^2, with none of the prime factors > 7. 1715 = 5 * 7^3 is present, as sigma(1715) = 2400 = 2^5 * 3 * 5^2. PROG (PARI) isA336354(n) = ((0==A336352(n))&&(1==A319988(n)); CROSSREFS Intersection of A070003 and A336353. Cf. A000203, A006530, A319988, A336352. Sequence in context: A045130 A045269 A043395 * A269346 A202852 A117689 Adjacent sequences: A336351 A336352 A336353 * A336355 A336356 A336357 KEYWORD nonn AUTHOR Antti Karttunen, Jul 19 2020 STATUS approved

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Last modified March 23 10:58 EDT 2023. Contains 361443 sequences. (Running on oeis4.)