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

3, 3, 5, 5, 11, 17, 353, 431, 509, 587, 13297, 21937, 30577, 39217, 47857, 1561423, 2716423, 3871423, 5026423, 6181423, 7336423, 291461857, 373881397, 456300937, 538720477, 621140017, 703559557, 785979097

Offset

1,1

Comments

Suggested by Charles R Greathouse IV in A278735.

The first set of 4 prime-indexed primes in arithmetic progression (353, 431, 509, and 587) contains consecutive terms of A142160.

The first set of 5 prime-indexed primes in arithmetic progression contains 3 numbers that are anagrams of each other (13297, 21937, and 39217).

Links

Table of n, a(n) for n=1..28.

Example

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.
The triangle begins:
3;
3, 5;
5, 11, 17;
353, 431, 509, 587;
13297, 21937, 30577, 39217, 47857;
1561423, 2716423, 3871423, 5026423, 6181423, 7336423;
...

Crossrefs

Cf. A006450, A133277, A142160, A274825, A278735, A279062.

Sequence in context: A286759 A146245 A245144 * A339555 A213029 A348843

Adjacent sequences: A279018 A279019 A279020 * A279022 A279023 A279024

Keyword

nonn,hard,more,tabl

Author

Bobby Jacobs, Dec 03 2016

Extensions

a(22)-a(28) from Charles R Greathouse IV, Dec 27 2016

Status

approved