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A154298 Primes of the form (1+...+m)/33 = A000217(m)/33, for some m. 2
2, 7, 17, 67 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes which are some triangular number A000217 divided by 33. Finiteness is shown with the same strategy as in A154297.

Original definition: Primes of the form : 1/x+2/x+3/x+4/x+5/x+6/x+7/x+..., x=33.

The corresponding m-values are m=11, 21, 33, 66 (cf. A154296).  It is clear that for m>66, A000217(m)/33 = m(m+1)/66 cannot be a prime. - M. F. Hasler, Dec 31 2012

LINKS

Table of n, a(n) for n=1..4.

MATHEMATICA

lst={}; s=0; Do[s+=n/33; If[Floor[s]==s, If[PrimeQ[s], AppendTo[lst, s]]], {n, 0, 9!}]; lst

PROG

(PARI) select(x->denominator(x)==1 & isprime(x), vector(66, m, m^2+m)/66)  \\ - M. F. Hasler, Dec 31 2012

CROSSREFS

Cf. A057570, A154293, A154296 - A154304.

Sequence in context: A182667 A067602 A216389 * A225806 A283754 A122382

Adjacent sequences:  A154295 A154296 A154297 * A154299 A154300 A154301

KEYWORD

nonn,fini,full,easy

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jan 06 2009

EXTENSIONS

Edited by M. F. Hasler, Dec 31 2012

STATUS

approved

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Last modified December 9 08:41 EST 2021. Contains 349627 sequences. (Running on oeis4.)