OFFSET
1,2
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..2049
FORMULA
If p is an odd prime then a(p) = 3.
EXAMPLE
a(6) = 4 because T_6(x)+1 = 32x^6-48x^4+18x^2 = x^2*(4x^2-3)^2.
PROG
(PARI) p2 = 1; p1 = x; for (n = 1, 103, p = 2*x*p1 - p2; f = factor(p1 + 1); print(sum(i = 1, matsize(f)[1], f[i, 2]), " "); p2 = p1; p1 = p); \\ David Wasserman, Mar 03 2005
(PARI) A086374(n) = {vecsum(factor(polchebyshev(n, 1, x)+1)[, 2])}; \\ Antti Karttunen, Sep 27 2018, after Andrew Howroyd's program for A086369
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Yuval Dekel (dekelyuval(AT)hotmail.com), Sep 06 2003
EXTENSIONS
More terms from David Wasserman, Mar 03 2005
STATUS
approved