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A098220 a(n) = floor(sigma(sigma(p))/p) = floor(sigma(p+1)/p) = floor(A008333(n)/p), where p is the n-th prime number. 4
2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 1, 2, 1, 2, 2, 2, 1, 1, 2, 1, 2, 2, 2, 1, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1, 1, 1, 2, 2, 3, 1, 2, 1, 2, 2, 1, 2, 2, 1, 2, 3, 1, 2, 2, 2, 2, 2, 1, 2, 1, 2, 2, 2, 1, 2, 1, 1, 2, 2, 2, 3, 2, 1, 2, 2, 2, 1, 2, 1, 3, 1, 2, 1, 2, 2, 2, 1, 2, 2, 2, 3, 1, 2, 2, 3, 2, 2, 1, 1, 1, 2, 2, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Values of these quotients are expectedly lower than ratios of A051027(n)/n.

LINKS

Table of n, a(n) for n=1..105.

EXAMPLE

For n = 7, the seventh prime is 17, so a(7) = floor(sigma(sigma(17))/17) = floor(sigma(18)/17) = floor(39/17) = 2.

PROG

(PARI) a(n) = my(p=prime(n)); sigma(p+1)\p; \\ Michel Marcus, Dec 23 2018

CROSSREFS

Cf. A000203, A051027, A008333, A098219, A098221, A098222.

Sequence in context: A102300 A202146 A087010 * A297032 A346953 A235508

Adjacent sequences:  A098217 A098218 A098219 * A098221 A098222 A098223

KEYWORD

nonn

AUTHOR

Labos Elemer, Oct 25 2004

STATUS

approved

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Last modified July 4 17:39 EDT 2022. Contains 355083 sequences. (Running on oeis4.)