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A077022 Values of n such that sum of first n primes squared is divisible by n-th prime. 1
1, 6, 17, 11156, 16548 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Remainder, a(n), when sum of first n primes squared is divided by n-th prime in A072004. In A072004, in three cases, a(n)=0 that is the sum of squares of first n primes is divisible by n-th prime. Here we added two more cases when a(n)=0.

a(6) > 10^11. - Giovanni Resta, Mar 07 2013

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

6 is OK because (p(1)^2+...+p(6)^2)/p(6)=29; 17 is OK because (p(1)^2+...+p(17)^2)/p(17)=284; 11156 is OK because (p(1)^2+...+p(11156)^2)/p(11156)=410066261; 16548 is OK because (p(1)^2+...+p(16548 )^2)/p(16548)=941945317.

MATHEMATICA

Module[{nn=17000, prs}, prs=Accumulate[Prime[Range[nn]]^2]; Select[Range[ nn], Divisible[prs[[#]], Prime[#]]&]] (* Harvey P. Dale, Nov 23 2013 *)

CROSSREFS

Cf. A072004, A077023.

Sequence in context: A099436 A209482 A209341 * A074923 A093061 A264028

Adjacent sequences:  A077019 A077020 A077021 * A077023 A077024 A077025

KEYWORD

nonn

AUTHOR

Randy L. Ekl and Zak Seidov, Oct 17 2002

STATUS

approved

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Last modified December 6 13:45 EST 2021. Contains 349563 sequences. (Running on oeis4.)