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A014852 Numbers n such that n divides s(n), where s(1)=1, s(k)=5*s(k-1)+k. 0
1, 5, 55, 355, 605, 3905, 6655, 25205, 42955, 73205, 201995, 277255, 472505 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The sequence so far (for n > 1) is the smallest terms of the values of (5 * 11^i * 71^j) for i,j >= 0. Is there another term (prime?) in the product or can it be proved that all entries have this form?

LINKS

Table of n, a(n) for n=1..13.

PROG

(PARI) lista(nn) = {nb = 1000; for (n=1, nn, v = vector(nb, i, (5^(i+(n-1)*nb+1)-4*(i+(n-1)*nb)-5)/(16*(i+(n-1)*nb))); w = select(n->(type(n) == "t_INT"), v, 1); for (k=1, #w, print1(w[k]+(n-1)*nb, ", ")); kill(v); ); } \\ Michel Marcus, May 31 2014

CROSSREFS

s(n) = A014827(n).

Sequence in context: A014700 A103326 A060558 * A144893 A015266 A138163

Adjacent sequences:  A014849 A014850 A014851 * A014853 A014854 A014855

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Olivier Gérard

EXTENSIONS

Comment and more terms from Larry Reeves (larryr(AT)acm.org), Mar 24 2000

a(10)-a(13) from Michel Marcus, May 31 2014

STATUS

approved

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Last modified January 24 19:19 EST 2020. Contains 331211 sequences. (Running on oeis4.)