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 A333115 a(n) is the least prime p such that A001222(p+n) = A001222(p-n) = n. 0
 23, 47, 1621, 373, 2352631, 9241, 18235603, 21968759, 27575049743, 2794997, 32503712890637, 304321037, 390917388671861, 277829661054961, 14392115869140641, 442395934703 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS a(10) <= 311346179693. a(11) = 2794997. a(18) > 7*10^12, a(19) = 1040573169683. - Giovanni Resta, Mar 08 2020 LINKS EXAMPLE a(3) = 47 is prime; 47-3 = 44 = 2^2*11 and 47+3 = 50 = 2*5^2 both have 3 prime divisors with multiplicity. MAPLE f:= proc(n) local k;       for k from n+1+(n mod 2) by 2 to 3*10^6+1 do         if isprime(k) and numtheory:-bigomega(k-n)=n and            numtheory:-bigomega(k+n)=n then return k         fi od;       FAIL end proc: map(f, [\$2..7]); MATHEMATICA Table[SelectFirst[Prime@ Range@ 2000000, PrimeOmega[#-n] == n && PrimeOmega[#+n] == n &], {n, 2, 8}] (* Robert Price, Sep 16 2020 *) PROG (PARI) a(n) = forprime(p=n+1, oo, if(bigomega(p-n)==n && bigomega(p+n)==n, return(p))); \\ Jinyuan Wang, Mar 08 2020 CROSSREFS Cf. A001222. Sequence in context: A157358 A158238 A328799 * A042056 A087807 A044100 Adjacent sequences:  A333112 A333113 A333114 * A333116 A333117 A333118 KEYWORD nonn,more AUTHOR J. M. Bergot and Robert Israel, Mar 07 2020 EXTENSIONS a(8)-a(9) from Jinyuan Wang, Mar 08 2020 a(10)-a(17) from Giovanni Resta, Mar 08 2020 STATUS approved

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Last modified July 1 03:30 EDT 2022. Contains 354947 sequences. (Running on oeis4.)