cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A321995 Indices of highly composite numbers A002182 which are between a twin prime pair.

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%I A321995 #18 Dec 03 2020 06:57:52
%S A321995 3,4,5,9,11,12,20,28,30,84,108,118,143,149,208,330,362,1002,2395,3160,
%T A321995 10535
%N A321995 Indices of highly composite numbers A002182 which are between a twin prime pair.
%C A321995 The highly composite numbers are listed in A068507, but their growth is such that one cannot list the terms beyond A002182(362), corresponding to a(17), in the DATA section.
%C A321995 The term a(21) corresponds to A002182(10535) = A108951(52900585920). - _Daniel Suteu_, Jun 27 2019
%C A321995 a(22) > 779674, if it exists. - _Amiram Eldar_, Dec 03 2020
%F A321995 Intersection of A306587 and A306588. - _Daniel Suteu_, Jun 27 2019
%o A321995 (PARI) select( x->ispseudoprime(x-1)&&ispseudoprime(x+1), A2182, 1) \\ assuming A2182 holds enough terms of A002182. - _M. F. Hasler_, Jun 23 2019
%Y A321995 Cf. A068507, A002182, A002822.
%K A321995 nonn,more
%O A321995 1,1
%A A321995 _M. F. Hasler_, Jun 23 2019
%E A321995 a(21) from _Daniel Suteu_, Jun 27 2019 (obtained from A. Flammenkamp's data)