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A075986 Numerator of 1+1/p(1)^2+ ... + 1/p(n)^2 where p(k) = k-th prime. 6
1, 5, 49, 1261, 62689, 7629469, 1294716361, 375074829229, 135662633811769, 71859617272521901, 60483708554835755641, 58166700851687469003901, 79670437976161330893757369, 133981073592392620630139873389 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

The sum is similar to that in A061015 with an additional 1. The sum in the definition has limit about 1.45224742. The case of reciprocal cubes is in A075987.

For n>0 a(n) is the determinant of the n X n matrix with elements M[i,j] = 1+Prime[i]^2 if i=j and 1 otherwise. - Alexander Adamchuk (alex(AT)kolmogorov.com), Jul 08 2006

REFERENCES

S. R. Finch, Mathematical Constants, Cambridge, 2003, pp. 94-98.

LINKS

S. R. Finch, Meissel-Mertens Constants

FORMULA

a(0)=1; a(n)=a(n-1)*p(n)^2+(p(1)*...*p(n-1))^2.

a(n) = Det[DiagonalMatrix[Table[Prime[i]^2,{i,1,n}]]+1] for n>0. - Alexander Adamchuk (alex(AT)kolmogorov.com), Jul 08 2006

EXAMPLE

a(2) = 49 so a(3) = 49*p(3)^2 + (2*3)^2 = 49*25 + 36 = 1261.

MATHEMATICA

Table[Det[DiagonalMatrix[Table[Prime[i]^2, {i, 1, n}]]+1], {n, 1, 15}] - Alexander Adamchuk (alex(AT)kolmogorov.com), Jul 08 2006

CROSSREFS

Cf. A061015, A075987, A024528.

Sequence in context: A001819 A064618 A193199 * A084765 A203411 A082795

Adjacent sequences:  A075983 A075984 A075985 * A075987 A075988 A075989

KEYWORD

nonn,frac

AUTHOR

Zak Seidov (zakseidov(AT)yahoo.com), Sep 28 2002

EXTENSIONS

Edited by Dean Hickerson (dean.hickerson(AT)yahoo.com), Sep 30 2002

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Last modified February 14 02:39 EST 2012. Contains 205567 sequences.