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A117619 a(n) = n^2 + 7. 10
7, 8, 11, 16, 23, 32, 43, 56, 71, 88, 107, 128, 151, 176, 203, 232, 263, 296, 331, 368, 407, 448, 491, 536, 583, 632, 683, 736, 791, 848, 907, 968, 1031, 1096, 1163, 1232, 1303, 1376, 1451, 1528, 1607, 1688, 1771, 1856, 1943, 2032, 2123, 2216, 2311, 2408 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Ivan Panchenko, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (3,-3,1).

FORMULA

G.f.: (-8*x^2 + 13*x - 7)/(x - 1)^3. - Indranil Ghosh, Apr 05 2017

From Amiram Eldar, Nov 02 2020: (Start)

Sum_{n>=0} 1/a(n) = (1 + sqrt(7)*Pi*coth(sqrt(7)*Pi))/14.

Sum_{n>=0} (-1)^n/a(n) = (1 + sqrt(7)*Pi*cosech(sqrt(7)*Pi))/14. (End)

MATHEMATICA

Table[n^2 + 7, {n, 0, 60}] (* Stefan Steinerberger, Apr 08 2006 *)

PROG

(PARI) a(n) = n^2 + 7 \\ Indranil Ghosh, Apr 05 2017

(Python) def a(n): return n**2 + 7 # Indranil Ghosh, Apr 05 2017

CROSSREFS

Cf. A117951, A117950.

Sequence in context: A090385 A145826 A102963 * A226977 A098731 A294483

Adjacent sequences:  A117616 A117617 A117618 * A117620 A117621 A117622

KEYWORD

nonn,less,easy

AUTHOR

Parthasarathy Nambi, Apr 07 2006

EXTENSIONS

More terms from Stefan Steinerberger, Apr 08 2006

STATUS

approved

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Last modified November 30 04:01 EST 2020. Contains 338781 sequences. (Running on oeis4.)