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A263549 Numbers k such that k divides the sum of the first k primes with odd indices. 0
1, 3, 67, 141, 2201, 2625, 8153, 10187, 11089, 136515, 138377, 1543419, 1712109, 5097739, 51562297, 1459124841 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) is always an odd number since the first prime is 2.

How do a(n) and A263546(n) compare asymptotically?

LINKS

Table of n, a(n) for n=1..16.

EXAMPLE

1 is in the sequence because prime(1) = 2 is divisible by 1.

3 is in the sequence because prime(1) + prime(3) + prime(5) = 2 + 5 + 11 = 18 is divisible by 3.

MATHEMATICA

Select[Range@ 10000, Divisible[Sum[Prime[2 i - 1], {i, 1, #}], #] &] (* Michael De Vlieger, Oct 21 2015 *)

PROG

(PARI) list(lim)=my(v=List(), k, s, t); forprime(p=2, , if((t++) && t%2==1, s+=p; k++; if(s%k==0, listput(v, k)); if(k>=lim, return(Vec(v)))))

CROSSREFS

Cf. A045345, A077131, A263541, A263546.

Sequence in context: A142035 A142926 A041983 * A225191 A201857 A294395

Adjacent sequences:  A263546 A263547 A263548 * A263550 A263551 A263552

KEYWORD

nonn,more

AUTHOR

Altug Alkan, Oct 21 2015

STATUS

approved

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Last modified November 15 09:03 EST 2019. Contains 329144 sequences. (Running on oeis4.)