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Highly composite numbers sandwiched between twin primes.
11

%I #31 Nov 06 2021 00:27:35

%S 4,6,12,60,180,240,7560,55440,110880,73329656400,18632716502400,

%T 130429015516800,48519593772249600,149602080797769600,

%U 74377068101903920953600,927967188666725711881005276648000,241271469053348685089061371928480000

%N Highly composite numbers sandwiched between twin primes.

%C Intersection of (A072826 - 1) and (A072828 + 1). - _Lekraj Beedassy_, Nov 27 2003

%C The next term, a(18), is A002182(1002), it has 77 digits. - _M. F. Hasler_, Jun 23 2019

%C a(22) > 10^17030, if it exists. - _Amiram Eldar_, Dec 03 2020

%H M. F. Hasler and Amiram Eldar, <a href="/A068507/b068507.txt">Table of n, a(n) for n = 1..21</a> (terms 1..20 from M. F. Hasler)

%H Brian Hayes, <a href="http://bit-player.org/2021/does-having-prime-neighbors-make-you-more-composite">Does having prime neighbors make you more composite?</a>, Bit-Player Article, Nov 04 2021

%F a(n) = A002182(A321995(n)). - _Amiram Eldar_, Dec 03 2020

%e 60 is between 59 and 61.

%Y Cf. A002182, A072826, A072828, A117825, A321995.

%Y This is also the intersection of A002182 and A014574.

%K nonn

%O 1,1

%A _Lekraj Beedassy_, Mar 25 2002

%E Corrected and extended by _Lior Manor_ Jun 03 2002

%E More terms from _Bill McEachen_, May 24 2006

%E a(18)-a(20) from _M. F. Hasler_, Jun 23 2019