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 A293221 a(n) = Product_{d|n, d
 1, 2, 2, 2, 2, 6, 2, 12, 6, 6, 2, 36, 2, 4, 18, 12, 2, 30, 2, 360, 12, 10, 2, 540, 6, 60, 30, 360, 2, 900, 2, 120, 30, 10, 12, 2700, 2, 4, 180, 360, 2, 540, 2, 360, 450, 6, 2, 5400, 4, 120, 30, 360, 2, 210, 30, 5040, 12, 14, 2, 1701000, 2, 84, 180, 2520, 180, 1260, 2, 840, 18, 12600, 2, 94500, 2, 140, 180, 840, 20, 18900, 2, 756000, 210, 210, 2, 23814000, 30 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Antti Karttunen, Table of n, a(n) for n = 1..6561 FORMULA a(n) = Product_{d|n, d= 0, a(3^n) = A002110(n). PROG (PARI) A019565(n) = {my(j, v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ This function from M. F. Hasler A289813(n) = { my (d=digits(n, 3)); fromdigits(vector(#d, i, if (d[i]==1, 1, 0)), 2); } \\ From _Remy Sigrist_ A293221(n) = { my(m=1); fordiv(n, d, if(d < n, m *= A019565(A289813(d)))); m; }; CROSSREFS Cf. A019565, A289813, A293214, A293222, A293223 (restricted growth sequence transform), A293226. Cf. also A290091. Sequence in context: A080400 A328236 A119462 * A334512 A096625 A263455 Adjacent sequences:  A293218 A293219 A293220 * A293222 A293223 A293224 KEYWORD nonn,base AUTHOR Antti Karttunen, Oct 03 2017 STATUS approved

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Last modified August 4 14:04 EDT 2020. Contains 336201 sequences. (Running on oeis4.)