This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A255186 27-gonal numbers: a(n) = n*(25*n-23)/2. 7
 0, 1, 27, 78, 154, 255, 381, 532, 708, 909, 1135, 1386, 1662, 1963, 2289, 2640, 3016, 3417, 3843, 4294, 4770, 5271, 5797, 6348, 6924, 7525, 8151, 8802, 9478, 10179, 10905, 11656, 12432, 13233, 14059, 14910, 15786, 16687, 17613, 18564, 19540 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS See comments in A255184. REFERENCES E. Deza and M. M. Deza, Figurate numbers, World Scientific Publishing (2012), page 6 (25th row of the table). LINKS Luciano Ancora, Table of n, a(n) for n = 0..1000 Index entries for linear recurrences with constant coefficients, signature (3,-3,1). FORMULA G.f.: x*(-1 - 24*x)/(-1 + x)^3. a(n) =  A000217(n) + 24*A000217(n-1). MATHEMATICA Table[n (25 n - 23)/2, {n, 40}] PROG (PARI) a(n)=n*(25*n-23)/2 \\ Charles R Greathouse IV, Jun 17 2017 CROSSREFS Cf. similar sequences listed in A255184. Sequence in context: A044165 A044546 A217966 * A121737 A124726 A126381 Adjacent sequences:  A255183 A255184 A255185 * A255187 A255188 A255189 KEYWORD nonn,easy AUTHOR Luciano Ancora, Apr 04 2015 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 15 22:25 EDT 2019. Contains 328038 sequences. (Running on oeis4.)