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 A083947 Integer coefficients of A(x), where 1<=a(n)<=7, such that A(x)^(1/7) consists entirely of integer coefficients. 12
 1, 7, 7, 7, 7, 7, 7, 1, 7, 7, 7, 7, 7, 7, 5, 7, 7, 7, 7, 7, 7, 1, 7, 7, 7, 7, 7, 7, 1, 7, 7, 7, 7, 7, 7, 4, 7, 7, 7, 7, 7, 7, 2, 7, 7, 7, 7, 7, 7, 1, 7, 7, 7, 7, 7, 7, 1, 7, 7, 7, 7, 7, 7, 3, 7, 7, 7, 7, 7, 7, 5, 7, 7, 7, 7, 7, 7, 1, 7, 7, 7, 7, 7, 7, 2, 7, 7, 7, 7, 7, 7, 5, 7, 7, 7, 7, 7, 7, 1, 7, 7, 7, 7, 7, 7 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS More generally the sequence, "integer coefficients of A(x), where 1<=a(n)<=m, such that A(x)^(1/m) consists entirely of integer coefficients", appears to have a unique solution for all m. Are these sequences periodic? LINKS Robert G. Wilson v, Table of n, a(n) for n = 0..3000. MATHEMATICA a[0] = 1; a[n_] := a[n] = Block[{k = 1, s = Sum[a[i]*x^i, {i, 0, n-1}]}, While[ Union[ IntegerQ /@ CoefficientList[ Series[(s+k*x^n)^(1/7), {x, 0, n}], x]] != {True}, k++ ]; k]; Table[ a[n], {n, 0, 104}] (* Robert G. Wilson v *) CROSSREFS Cf. A083952, A083953, A083954, A083955, A083956, A083948, A083949, A083950. Sequence in context: A103983 A232127 A195413 * A269349 A112114 A031182 Adjacent sequences:  A083944 A083945 A083946 * A083948 A083949 A083950 KEYWORD nonn AUTHOR Paul D. Hanna, May 09 2003 EXTENSIONS More terms from Robert G. Wilson v, Jul 26 2005 STATUS approved

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Last modified June 17 19:57 EDT 2021. Contains 345085 sequences. (Running on oeis4.)