A139619 a(n) = 171*n + 19.

19, 190, 361, 532, 703, 874, 1045, 1216, 1387, 1558, 1729, 1900, 2071, 2242, 2413, 2584, 2755, 2926, 3097, 3268, 3439, 3610, 3781, 3952, 4123, 4294, 4465, 4636, 4807, 4978, 5149, 5320, 5491, 5662, 5833, 6004, 6175, 6346, 6517, 6688

Offset

0,1

Comments

Numbers of the 19th column of positive numbers in the square array of nonnegative and polygonal numbers A139600. Also, numbers of the 19th column in the square array A057145.

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..5000

Index entries for linear recurrences with constant coefficients, signature (2,-1).

Formula

From Chai Wah Wu, Apr 14 2017: (Start)

a(n) = 2*a(n-1) - a(n-2) for n > 1.

G.f.: (152*x + 19)/(x - 1)^2. (End)

From Elmo R. Oliveira, Apr 11 2024: (Start)

E.g.f.: 19*exp(x)*(1 + 9*x).

a(n) = 19*A017173(n) = 19*(A051682(n+1) - A051682(n)). (End)

Mathematica

Range[0, 100]*171 + 19 (* Paolo Xausa, Apr 17 2024 *)

Prog

(Magma) [19*(9*n + 1): n in [0..50]]; // Vincenzo Librandi, Jul 23 2011
(PARI) a(n)=171*n+19 \\ Charles R Greathouse IV, Oct 05 2011

Crossrefs

Cf. A016957, A017329, A057145, A139600, A139606-A139618, A139620.

Cf. A017173, A051682.

Sequence in context: A162347 A161879 A176600 * A121039 A162639 A247614

Adjacent sequences: A139616 A139617 A139618 * A139620 A139621 A139622

Keyword

easy,nonn,changed

Author

Omar E. Pol, May 21 2008

Status

approved