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A131991 a(n) = 1 + prime(n) + prime(n)^2 + prime(n)^3. 8
15, 40, 156, 400, 1464, 2380, 5220, 7240, 12720, 25260, 30784, 52060, 70644, 81400, 106080, 151740, 208920, 230764, 305320, 363024, 394420, 499360, 578760, 712980, 922180, 1040604, 1103440, 1236600, 1307020, 1455780, 2064640, 2265384 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = 1 + A060800(n)*A000040(n).

a(n) = (A030514(n) - 1)/A006093(n).

a(n) = A000203(A000040(n)^3). - Zak Seidov, Feb 13 2016

EXAMPLE

a(4)=400 because the 4th prime is 7, 7^3=343, 7^2=49, and 343+49+7+1=400.

MAPLE

A131991:= n -> map (p -> p^(3)+p^(2)+p+1, ithprime(n)):

seq (A131991(n), n=1..32); # Jani Melik, Jan 25 2011

MATHEMATICA

#^3 + #^2 + # + 1 &/@Prime[Range[100]] (* Vincenzo Librandi, Mar 20 2014 *)

PROG

(MAGMA) [1+NthPrime(n)+NthPrime(n)^2+NthPrime(n)^3: n in [1..40]]; // Vincenzo Librandi, Dec 27 2010

CROSSREFS

Cf. A030078, A008864, A131992, A131993.

Cf. A000040, A000203. - Zak Seidov, Feb 13 2016

Sequence in context: A175926 A038991 A068020 * A116042 A219378 A280045

Adjacent sequences:  A131988 A131989 A131990 * A131992 A131993 A131994

KEYWORD

nonn,easy

AUTHOR

Reinhard Zumkeller, Aug 06 2007

STATUS

approved

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Last modified May 24 22:11 EDT 2017. Contains 287008 sequences.