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A165660 Denominators of A007504 divided by A033955, starting from the second term of A033955. 3
1, 3, 2, 8, 13, 18, 27, 29, 23, 56, 7, 74, 44, 98, 67, 49, 171, 200, 217, 28, 137, 309, 17, 116, 209, 448, 471, 174, 571, 629, 137, 739, 111, 793, 853, 318, 997, 1002, 560, 164, 610, 446, 1419, 1466, 385, 1615, 1573, 1633, 1707, 1825, 946, 662, 2221, 781, 1198 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Conjecture: with the exception of the second term, 2 <= A165659(n)/a(n) < 3.

LINKS

Table of n, a(n) for n=1..55.

PROG

(PARI) a1(n)=sum(i=1, n, prime(i)); b1(n)=sum(i=1, n, prime(n+1)%prime(i)); a(n)=if(n<0, 0, denominator(a1(n)/b1(n))); for(n=1, 50, print1(a(n) ", "))

CROSSREFS

Cf. A007504, A033995, A002110, A102647, A165657, A165658, A165659

Sequence in context: A094188 A088551 A301903 * A171634 A107300 A285787

Adjacent sequences:  A165657 A165658 A165659 * A165661 A165662 A165663

KEYWORD

easy,nonn

AUTHOR

Creighton Dement, Sep 24 2009

EXTENSIONS

Terms corrected by Creighton Dement, Oct 03 2009

Removed a conjecture - R. J. Mathar, Oct 09 2009

Typo in definition corrected by Creighton Dement, Oct 09 2009

STATUS

approved

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Last modified January 21 13:55 EST 2020. Contains 331113 sequences. (Running on oeis4.)