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 A157895 Coefficients of polynomials of a prime like factor set : p(x,n)=Sum[x^i, {i, 0, (Prime[n] - 1)/2}]; q(n,n)=Sum[(-1)^i*x^i, {i, 0, (Prime[n] - 1)/2}]; t(x,n)=If[n == 0, 1, If[n == 1, x + 1, (x + 1)*p[x, n]*q[x, n]]]. 0
 1, 1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1, 1, 1, 1, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Row sums are: {1, 2, 0, 6, 0, 0, 14, 18, 0, 0, 30, 0, 38, 42, 0, 0, 54, 0, 62, 0, 0,...}. This row sum minus one picks out as cyclotomic the primes; A002144: {5,13,17,29,37,41,53,61,...} LINKS FORMULA p(x,n)=Sum[x^i, {i, 0, (Prime[n] - 1)/2}]; q(n,n)=Sum[(-1)^i*x^i, {i, 0, (Prime[n] - 1)/2}]; t(x,n)=If[n == 0, 1, If[n == 1, x + 1, (x + 1)*p[x, n]*q[x, n]]]; out_(n,m)=coefficients(t(x,n)). EXAMPLE {1}, {1, 1}, {1, 1, -1, -1}, {1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, -1, -1, -1, -1}, {1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1} MATHEMATICA Clear[p, q, t, x, n]; p[x_, n_] := Sum[x^i, {i, 0, (Prime[n] - 1)/2}]; q[x_, n_] := Sum[(-1)^i*x^i, {i, 0, (Prime[n] - 1)/2}]; t[x_, n_] := If[n == 0, 1, If[n == 1, x + 1, (x + 1)*p[x, n]*q[x, n]]]; Table[ExpandAll[t[x, n]], {n, 0, 10}]; Table[CoefficientList[ExpandAll[t[x, n]], x], {n, 0, 10}]; Flatten[%] CROSSREFS Sequence in context: A232544 A309873 A162511 * A063747 A077008 A158387 Adjacent sequences:  A157892 A157893 A157894 * A157896 A157897 A157898 KEYWORD sign,tabl,uned AUTHOR Roger L. Bagula, Mar 08 2009 STATUS approved

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Last modified May 9 10:48 EDT 2021. Contains 343732 sequences. (Running on oeis4.)