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A192503 Ludic prime numbers. 5
2, 3, 5, 7, 11, 13, 17, 23, 29, 37, 41, 43, 47, 53, 61, 67, 71, 83, 89, 97, 107, 127, 131, 149, 157, 173, 179, 181, 193, 211, 223, 227, 233, 239, 257, 277, 283, 307, 313, 331, 337, 353, 359, 383, 389, 397, 419, 421, 431, 433, 463, 467, 503, 509, 541, 577 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A000040 and A003309; A010051(a(n))*A192490(a(n)) = 1.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

PROG

(Haskell)

a192503 n = a192503_list !! (n-1)

a192503_list = filter ((== 1) . a010051) a003309_list

(PARI) A192503(maxn, bflag=0)={my(Vw=vector(maxn, x, x+1), Vl=Vec([1]), vwn=#Vw, i, vj, L=List());

while(vwn>0, i=Vw[1]; Vl=concat(Vl, [i]);

      Vw=vector((vwn*(i-1))\i, x, Vw[(x*i+i-2)\(i-1)]); vwn=#Vw);

kill(Vw); vwn=#Vl;

for(j=1, vwn, vj=Vl[j]; if(isprime(vj), listput(L, vj))); kill(Vw); vwn=#L;

if(bflag, for(i=1, vwn, print(i, " ", L[i]))); if(!bflag, return(Vec(L)));

} \\ Anatoly E. Voevudko, Feb 28 2016

CROSSREFS

Cf. A192506 (neither ludic nor prime).

Sequence in context: A162855 A194954 A299956 * A040067 A181659 A040087

Adjacent sequences:  A192500 A192501 A192502 * A192504 A192505 A192506

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 05 2011

STATUS

approved

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Last modified December 4 09:35 EST 2020. Contains 338923 sequences. (Running on oeis4.)