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 A322272 Smallest multiplication factors f, prime or 1, for all a (mod 120), coprime to 120, so that b*f is a nonzero square mod 8, mod 3, and mod 5. 6
 1, 7, 11, 13, 17, 19, 23, 29, 31, 13, 41, 43, 23, 1, 53, 11, 61, 43, 71, 73, 53, 31, 83, 41, 19, 73, 29, 7, 83, 61, 17, 71 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See sequence A322269 for further explanations. This sequence is related to A322269(3). The sequence is periodic, repeating itself after phi(120) terms. Its largest term is 83, which is A322269(3). In order to satisfy the conditions, both f and b must be coprime to 120. Otherwise, the product would be zero mod a prime <= 5. The b(n) corresponding to each a(n) is A007775(n). LINKS Table of n, a(n) for n=1..32. EXAMPLE The 10th number coprime to 120 is 37. a(10) is 13, because 13 is the smallest prime by which we can multiply 37, so that the product (37*13 = 481) is a square mod 8, mod 3 and mod 5. PROG (PARI) QresCode(n, nPrimes) = { code = bitand(n, 7)>>1; for (j=2, nPrimes, x = Mod(n, prime(j)); if (issquare(x), code += (1<

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Last modified May 19 19:45 EDT 2024. Contains 372703 sequences. (Running on oeis4.)