A239564 a(n) = (round(c^prime(n)) - 1)/prime(n), where c is the pentanacci constant (A103814).

154, 504, 5758, 19912, 245714, 11251030, 40679232, 1967728552, 26525975822, 97753187576, 1335948880418, 68398141417510, 3547322151373882, 13260715720748120, 697034813138756392, 9825603574709578482, 36935066391752894480, 1970457739485406707872

Offset

5,1

Comments

For n>=5, round(c^prime(n)) == 1 (mod 2*prime(n)). Proof in Shevelev link. In particular, all terms are even.

Links

Table of n, a(n) for n=5..22.

S. Litsyn and Vladimir Shevelev, Irrational Factors Satisfying the Little Fermat Theorem, International Journal of Number Theory, vol.1, no.4 (2005), 499-512.

Vladimir Shevelev, A property of n-bonacci constant, Seqfan (Mar 23 2014)

Eric Weisstein's World of Mathematics, Pentanacci Constant

Crossrefs

Cf. A000040, A007619, A007663, A238693, A238697, A238698, A238700, A103814, A239502, A239544.

Sequence in context: A320708 A261377 A256024 * A250626 A235107 A235100

Adjacent sequences: A239561 A239562 A239563 * A239565 A239566 A239567

Keyword

nonn

Author

Vladimir Shevelev and Peter J. C. Moses, Mar 21 2014

Status

approved