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 A186413 a(n) is the number of odd primes p < prime(n)^2 such that prime(n)# + p is prime with prime(n)# primorial of prime(n). 2
 1, 2, 5, 8, 16, 18, 20, 28, 25, 30, 40, 46, 41, 53, 56, 73, 62, 66, 81, 93, 85, 84, 89, 97, 101, 127, 121, 122, 119, 128, 150, 141, 144, 152, 150, 143, 174, 203, 197, 195, 196, 194, 213, 213, 218, 223, 230, 235, 249, 258, 256, 244, 264, 262 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) is not so far from prime(n). LINKS Pierre CAMI, Table of n, a(n) for n = 1..176 EXAMPLE prime(1)#=2 2+3=5 5>2^2 so a(1)=1 prime(2)#=6 6+5=11,6+7=13 11>3*3 so a(2)=2 PROG SCRIPT DIM nn, 1 DIM kk DIM cc DIM dd DIMS tt DIMS ss OPENFILEOUT myout, res LABEL loopn SET nn, nn+1 SET kk, nn SET cc, 0 SET dd, 0 LABEL loopk SET kk, kk+1 IF p(kk)>p(nn)^2 THEN GOTO a SETS tt, %d, %d, %d\,; nn; p(nn); -p(kk) PRP p(nn)#-p(kk), tt IF ISPRIME THEN SET cc, cc+1 IF ISPRP THEN SET cc, cc+1 SETS tt, %d, %d, %d\,; nn; p(nn); p(kk) PRP p(nn)#+p(kk), tt IF ISPRIME THEN SET dd, dd+1 IF ISPRP THEN SET dd, dd+1 GOTO loopk LABEL a SETS ss, %d, %d, %d\,; nn; cc; dd WRITE myout, ss GOTO loopn CROSSREFS Cf. A185398. Sequence in context: A285291 A065618 A257548 * A080084 A065093 A168470 Adjacent sequences:  A186410 A186411 A186412 * A186414 A186415 A186416 KEYWORD nonn AUTHOR Pierre CAMI, Feb 21 2011 STATUS approved

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Last modified November 14 23:06 EST 2018. Contains 317221 sequences. (Running on oeis4.)