A221946 a(n) = floor(sqrt(2*7^n)).

1, 3, 9, 26, 69, 183, 485, 1283, 3395, 8983, 23768, 62886, 166380, 440202, 1164665, 3081415, 8152659, 21569910, 57068618, 150989371, 399480328, 1056925602, 2796362297, 7398479214, 19574536080, 51789354498, 137021752562, 362525481486, 959152267937, 2537678370405, 6714065875561, 17763748592841

Offset

0,2

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Mathematica

Table[Floor[Sqrt[2*7^n]], {n, 0, 50}] (* G. C. Greubel, Jan 26 2018 *)

Prog

(PARI) a(n)=sqrtint(2*7^n) \\ Charles R Greathouse IV, Apr 18 2013
(Magma) [Floor(Sqrt(2*7^n)): n in [0..50]]; // G. C. Greubel, Jan 26 2018

Crossrefs

Cf. A017910, A017913, A017919, A114183, A221718, A221942-A221946.

Sequence in context: A055293 A034531 A258097 * A291410 A048470 A138237

Adjacent sequences: A221943 A221944 A221945 * A221947 A221948 A221949

Keyword

nonn

Author

N. J. A. Sloane, Feb 01 2013

Status

approved