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.

A061771 Primes p(k) such that p(k+1) - p(k) = 2^m for some m (smaller of a pair of consecutive primes which differ by a power of 2).

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%I A061771 #8 Apr 22 2019 15:52:35
%S A061771 2,3,5,7,11,13,17,19,29,37,41,43,59,67,71,79,89,97,101,103,107,109,
%T A061771 127,137,149,163,179,191,193,197,223,227,229,239,269,277,281,307,311,
%U A061771 313,347,349,359,379,389,397,401,419,431,439,449,457,461,463,479,487,491
%N A061771 Primes p(k) such that p(k+1) - p(k) = 2^m for some m (smaller of a pair of consecutive primes which differ by a power of 2).
%H A061771 Charles R Greathouse IV, <a href="/A061771/b061771.txt">Table of n, a(n) for n = 1..10000</a>
%e A061771 89 is a term as the next prime 97 differs from it by 8, a power of 2.
%t A061771 Select[Partition[Prime[Range[100]],2,1],IntegerQ[Log2[#[[2]]-#[[1]]]]&][[All,1]] (* _Harvey P. Dale_, Apr 22 2019 *)
%o A061771 (PARI) ispow2(n)=n>>valuation(n,2)==1
%o A061771 v=List();p=2;forprime(q=3,1e6,if(ispow2(q-p),listput(v,p));p=q); Vec(v) \\ _Charles R Greathouse IV_, Sep 18 2013
%K A061771 nonn,easy
%O A061771 1,1
%A A061771 _Amarnath Murthy_, May 22 2001
%E A061771 Extended by _Patrick De Geest_, May 27 2001