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A290781 a(n) = 20*n + 15. 1
15, 35, 55, 75, 95, 115, 135, 155, 175, 195, 215, 235, 255, 275, 295, 315, 335, 355, 375, 395, 415, 435, 455, 475, 495, 515, 535, 555, 575, 595, 615, 635, 655, 675, 695, 715, 735, 755, 775, 795, 815, 835, 855, 875, 895, 915, 935, 955, 975, 995, 1015, 1035 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Bisection of A017329.

None of the numbers in this sequence is a Fermat pseudoprime to base 2.

LINKS

Table of n, a(n) for n=0..51.

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

FORMULA

G.f.: 5*(3 + x)/(1 - x)^2.

a(n) = A004767(A016885(n)) = A004767(A004767(n) + n). - Torlach Rush, Oct 10 2019

E.g.f.: 5*exp(x)*(3 + 4*x). - Stefano Spezia, Oct 12 2019

MATHEMATICA

Range[15, 1035, 20]

PROG

(MAGMA) [n: n in [15..1035 by 20]];

CROSSREFS

Cf. A001567, A004767, A016885, A017329.

Sequence in context: A201018 A187400 A162280 * A063532 A212331 A067930

Adjacent sequences:  A290778 A290779 A290780 * A290782 A290783 A290784

KEYWORD

nonn,easy

AUTHOR

Arkadiusz Wesolowski, Aug 10 2017

STATUS

approved

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Last modified February 23 23:18 EST 2020. Contains 332195 sequences. (Running on oeis4.)