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 A306354 a(n) = gcd(n, A101337(n)). 2
 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 1, 2, 1, 4, 1, 2, 1, 4, 1, 3, 1, 1, 3, 1, 1, 9, 1, 1, 3, 8, 1, 2, 1, 4, 1, 2, 1, 16, 1, 25, 1, 1, 1, 1, 5, 1, 1, 1, 1, 12, 1, 2, 9, 4, 1, 6, 1, 4, 3, 7, 1, 1, 1, 1, 1, 1, 7, 1, 1, 16, 1, 2, 1, 4, 1, 2, 1, 8, 1, 9 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A101337(n) / n = r, r an integer, gives A306360. A101337(n) / n = 1 gives A005188. n / A101337(n) = s, s an integer, gives A306361. The motivation for this sequence was the question as to which numbers n have the property A101337(n) / n = r and the property n / A101337(n) = s? LINKS EXAMPLE For n = 24, a(24) = gcd(24, 2*2 + 4*4) = gcd(24,20) = 4, thus a(24) = 4; for n = 153, a(153) = gcd(153, 1*1*1 + 5*5*5 + 3*3*3) = gcd(153,153) = 153, thus a(153) = 153. MATHEMATICA Array[GCD[#1, Total[#2^Length[#2]]] & @@ {#, IntegerDigits@ #} &, 90] (* Michael De Vlieger, Feb 09 2019 *) PROG (PARI) a(n) = my(d=digits(n)); gcd(n, sum(i=1, #d, d[i]^#d)); \\ Michel Marcus, Feb 12 2019 CROSSREFS Cf. A005188, A066750, A101337. Sequence in context: A121042 A000030 A179635 * A216587 A174210 A134777 Adjacent sequences:  A306351 A306352 A306353 * A306355 A306356 A306357 KEYWORD nonn,base AUTHOR Ctibor O. Zizka, Feb 09 2019 STATUS approved

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Last modified February 27 15:09 EST 2020. Contains 332306 sequences. (Running on oeis4.)