A282326 Greater of twin primes congruent to 1 (mod 30).

31, 61, 151, 181, 241, 271, 421, 571, 601, 661, 811, 1021, 1051, 1231, 1291, 1321, 1621, 1951, 2131, 2311, 2341, 2551, 2731, 2791, 2971, 3001, 3121, 3301, 3331, 3361, 3391, 3541, 3931, 4021, 4051, 4231, 4261, 4651, 4801, 5011, 5101, 5281, 5521, 5641, 5851

Offset: 1

Author

Martin Renner, Feb 11 2017

Keywords

• nonn

Comments

The union of [A060229 and this sequence] is A132243.

The union of [{5, 7}, A282322, A282324 and this sequence] is the greater of twin primes sequence A006512.

The union of [{3, 5, 7}, A282321 to A060229 and this sequence] is the twin primes sequence A001097.

Number of terms less than 10^k, k=2,3,4,...: 2, 11, 72, 407, 2697, 19507, 146516, ... - Muniru A Asiru, Mar 05 2018

Links

• Muniru A Asiru, Table of n, a(n) for n = 1..10000

Crossrefs

Subset of A006512, A181603, A132230, A132243 and A132247.

Cf. A001359, A232880, A232881, A232882, A282321, A282322, A282323, A282324, A060229.

Programs

GAP

Filtered(List([0..300], k -> 30*k+1), n -> IsPrime(n-2) and IsPrime(n));  # Muniru A Asiru, Mar 05 2018

Maple

select(n -> isprime(n-2) and isprime(n), [seq(30*k+1, k=0..300)]); # Muniru A Asiru, Mar 05 2018

Mathematica

1 + Select[30 Range@ 200, AllTrue[# + {-1, 1}, PrimeQ] &] (* Michael De Vlieger, Mar 26 2018 *)

PARI

list(lim)=my(v=List(),p=2); forprime(q=3,lim, if(q-p==2 && q%30==1, listput(v,q)); p=q); Vec(v) \\ Charles R Greathouse IV, Feb 14 2017