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A103731 Column k=4 sequence of array A103728. 0
1, 13, 191, 457, 1713, 2899, 6997, 19769, 26521, 57313, 89161, 109327, 159713, 265617, 417079, 479641, 709963, 903981, 1014697, 1408369, 1727987, 2305689, 3287713, 3882401, 4208317, 4921263, 5309929, 6155857, 9930313, 11272171 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The two a(n) formulas, given below, produce natural numbers for all n>=0.

LINKS

Table of n, a(n) for n=0..29.

FORMULA

a(n)=A103728(n+3, 4)=(1 +(p(n+3)-1)*binomial(p(n+3)-1, 4))/p(n+3), with p(n):=A000040(n) (n-th prime).

a(n)= (74 - 85*p(n+3) + 45*p(n+3)^2 - 11*p(n+3)^3 + p(n+3)^4)/4! = sum(A103718(k, m)*p(n+3)^m, m=0..4)/4!.

CROSSREFS

Sequence in context: A318595 A055613 A123808 * A331495 A000563 A213698

Adjacent sequences:  A103728 A103729 A103730 * A103732 A103733 A103734

KEYWORD

nonn,easy

AUTHOR

Wolfdieter Lang, Feb 24 2005

STATUS

approved

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Last modified May 26 17:16 EDT 2022. Contains 354092 sequences. (Running on oeis4.)