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A082676
Constant term of polynomial of degree n passing through the first n+1 consecutive prime-indexed primes.
0
1, 5, 9, 21, 53, 129, 303, 695, 1543, 3251, 6375, 11411, 18113, 23877, 20517, -11385, -111285, -350599, -844759, -1752605, -3220485, -5146003, -6428481, -2891081, 17977615, 89400059, 292685805, 814545349, 2061282923, 4876315217, 10937900039, 23459793869, 48384441535, 96352980717
OFFSET
1,2
COMMENTS
Eventually some terms will be negative.
FORMULA
Prime-indexed primes (PIPs) are generated by prime(prime(x)) x = 1, 2, ...
EXAMPLE
For n = 3, the polynomial p(x) = (-2/3)x^3 + 6x^2 - (34/3)x + 9 satisfies p(1) = 3, p(2) = 5, p(3) = 11 and p(4) = 17, so a(3) = 9.
PROG
(PARI) for (i = 2, 50, x = vector(i); y = x; for (j = 1, i, y[j] = prime(prime(j)); x[j] = j); q = polinterpolate(x, y, 0); print(q))
CROSSREFS
Sequence in context: A083943 A097074 A050559 * A146932 A146476 A110200
KEYWORD
easy,sign
AUTHOR
Cino Hilliard, May 19 2003
EXTENSIONS
More terms from David Wasserman, Sep 23 2004
STATUS
approved