A258016 Unlucky numbers removed at the stage three of Lucky sieve.

19, 39, 61, 81, 103, 123, 145, 165, 187, 207, 229, 249, 271, 291, 313, 333, 355, 375, 397, 417, 439, 459, 481, 501, 523, 543, 565, 585, 607, 627, 649, 669, 691, 711, 733, 753, 775, 795, 817, 837, 859, 879, 901, 921, 943, 963, 985, 1005, 1027, 1047, 1069, 1089, 1111, 1131, 1153, 1173, 1195, 1215, 1237, 1257, 1279, 1299, 1321, 1341, 1363, 1383, 1405

Offset

1,1

Comments

Numbers congruent to 19 or 39 modulo 42. - Jianing Song, Apr 27 2022

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000

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

Formula

a(n) = A047241(7*n).

a(n) = A260436(A255413(1+n)).

From Jianing Song, Apr 27 2022: (Start)

a(n) = a(n-2) + 42.

a(n) = a(n-1) + a(n-2) - a(n-3).

G.f.: (19*x+20*x^2+3*x^3)/(1-x-x^2+x^3).

E.g.f.: 3 + (21*x-3)*cosh(x) + (21*x-2)*sinh(x). (End)

Prog

(Scheme, two alternatives)
(define (A258016 n) (A047241 (* n 7)))
(define (A258016 n) (A255543bi 3 n)) ;; Code for A255543bi given in A255543.

Crossrefs

Row 3 of A255543. Every seventh term of A047241.

Cf. also A258011.

Sequence in context: A042629 A041708 A079044 * A217731 A195048 A299964

Adjacent sequences: A258013 A258014 A258015 * A258017 A258018 A258019

Keyword

nonn,easy

Author

Antti Karttunen, Jul 27 2015

Status

approved