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A110436
A weighted sum of Jacobi function values.
3
1, 3, 7, 13, 31, 63, 105, 255, 511, 869, 2047, 3963, 7021, 16383, 32767, 56141, 125811, 262143, 449325, 1048575, 2097151, 3459945, 8388607, 16645111, 28760685, 67108863, 129822555, 230087021, 536870911, 1073741823, 1823791973
OFFSET
1,2
COMMENTS
It would appear that a(n)=2^m-1 if 2n+1 is prime.
FORMULA
a(n)=sum{k=0..n, abs(Jacobi(n-k, 2k+1))2^k}
CROSSREFS
Sequence in context: A119962 A333877 A220746 * A126879 A247895 A336688
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Jul 20 2005
STATUS
approved