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A342730 a(n) = floor((frac(e*n) + 1) * prime(n+1)). 2
2, 5, 7, 8, 20, 20, 22, 19, 40, 42, 36, 70, 66, 57, 49, 94, 88, 73, 129, 116, 99, 85, 149, 135, 120, 197, 172, 149, 121, 206, 196, 165, 271, 236, 211, 172, 291, 256, 216, 175, 309, 262, 223, 364, 316, 263, 219, 392, 335, 273, 445, 390, 325, 268, 459, 395 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..55.

Simon Strandgaard, Plot of 400 terms

EXAMPLE

x(n) = frac(e * n) + 1,

a(0) = floor(x(0) * prime(1)) = floor(1.00 *  2) =  2,

a(1) = floor(x(1) * prime(2)) = floor(1.72 *  3) =  5,

a(2) = floor(x(2) * prime(3)) = floor(1.44 *  5) =  7,

a(3) = floor(x(3) * prime(4)) = floor(1.15 *  7) =  8,

a(4) = floor(x(4) * prime(5)) = floor(1.87 * 11) = 20.

MATHEMATICA

Array[Floor[(Mod[E #, 1] + 1) Prime[# + 1]] &, 56, 0] (* Michael De Vlieger, Mar 19 2021 *)

PROG

(Ruby) require 'prime'

values = []

primes = Prime.first(20)

primes.each_with_index do |prime, n|

    x = ((n * Math::E) % 1) + 1

    values << (x * prime).floor

end

p values

(PARI) a(n) = floor((frac(exp(1)*n) + 1) * prime(n+1)); \\ Michel Marcus, Mar 20 2021

CROSSREFS

Cf. A000040, A001113.

Sequence in context: A340326 A188341 A238364 * A227445 A216968 A088757

Adjacent sequences:  A342727 A342728 A342729 * A342731 A342732 A342733

KEYWORD

nonn,look

AUTHOR

Simon Strandgaard, Mar 19 2021

STATUS

approved

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Last modified October 17 17:21 EDT 2021. Contains 348065 sequences. (Running on oeis4.)