cp's OEIS Frontend

A279021 Triangle read by rows, giving the arithmetic progressions of prime-indexed primes in A278735.

%I A279021 #46 Jan 04 2017 06:59:58
%S A279021 3,3,5,5,11,17,353,431,509,587,13297,21937,30577,39217,47857,1561423,
%T A279021 2716423,3871423,5026423,6181423,7336423,291461857,373881397,
%U A279021 456300937,538720477,621140017,703559557,785979097
%N A279021 Triangle read by rows, giving the arithmetic progressions of prime-indexed primes in A278735.
%C A279021 Suggested by _Charles R Greathouse IV_ in A278735.
%C A279021 The first set of 4 prime-indexed primes in arithmetic progression (353, 431, 509, and 587) contains consecutive terms of A142160.
%C A279021 The first set of 5 prime-indexed primes in arithmetic progression contains 3 numbers that are anagrams of each other (13297, 21937, and 39217).
%e A279021 a(7) = 353, a(8) = 431, a(9) = 509, and a(10) = 587 because 353 = prime(prime(20)), 431 = prime(prime(23)), 509 = prime(prime(25)), 587 = prime(prime(28)), and 431-353 = 509-431 = 587-509 = 78.
%e A279021 The triangle begins:
%e A279021 3;
%e A279021 3, 5;
%e A279021 5, 11, 17;
%e A279021 353, 431, 509, 587;
%e A279021 13297, 21937, 30577, 39217, 47857;
%e A279021 1561423, 2716423, 3871423, 5026423, 6181423, 7336423;
%e A279021 ...
%Y A279021 Cf. A006450, A133277, A142160, A274825, A278735, A279062.
%K A279021 nonn,hard,more,tabl
%O A279021 1,1
%A A279021 _Bobby Jacobs_, Dec 03 2016
%E A279021 a(22)-a(28) from _Charles R Greathouse IV_, Dec 27 2016