A145714 a(n) = ceiling(sqrt(2*A145701(n))).

3, 5, 6, 11, 12, 19, 25, 29, 42, 48, 65, 72, 79, 84, 90, 101, 174, 204, 205, 209, 221, 245, 264, 275, 289, 299, 306, 349, 371, 372, 408, 409, 415, 449, 456, 474, 521, 535, 546, 569, 571, 575, 594

Offset

1,1

Comments

If p_n is the n-th prime, then ceiling(sqrt(2p_n)) is in the sequence iff A145236(n) = A145236(n+1).

Links

Table of n, a(n) for n=1..43.

Maple

A145701 :=proc(n) local p; if n = 1 then return 3; end if; p := nextprime(procname(n-1)) ; while true do if isprime(p) and isprime(p+2) then if floor(sqrt(2*p)) <> floor( sqrt(2*p+4)) then return p; end if; end if; p := nextprime(p) ; end do; end proc:
A145714 := proc(n) ceil(sqrt(2*A145701(n))) ; end proc:
for n from 1 to 80 do printf("%d, \n", A145714(n)) ; end do; # R. J. Mathar, Aug 02 2010

Crossrefs

Cf. A145236, A145701.

Sequence in context: A001838 A285785 A080759 * A326310 A047443 A173593

Adjacent sequences: A145711 A145712 A145713 * A145715 A145716 A145717

Keyword

nonn

Author

Vladimir Shevelev, Oct 16 2008

Extensions

More terms from R. J. Mathar, Aug 02 2010

Status

approved