

A135275


a(n) = prime(2n1) + prime(2n)  prime(2n+1).


1



0, 1, 7, 13, 21, 27, 37, 41, 53, 65, 69, 75, 95, 101, 95, 121, 127, 143, 153, 161, 169, 187, 185, 207, 223, 231, 235, 251, 263, 275, 269, 305, 299, 321, 343, 345, 361, 373, 385, 391, 409, 425, 433, 445, 457, 459, 479, 493, 507, 517
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OFFSET

1,3


COMMENTS

Original name was: Sum and difference of staircase primes according to the rule: bottom + top  next top.


LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000


FORMULA

We list the primes in staircase fashion as in A135274. The right diagonal, RD(n), is the set of top primes and the left diagonal, LD(x), is the set of bottom primes. Then a(n) = LD(n+1) + RD(n)  RD(n+2).
a(n) = A096379(2*n1).  R. J. Mathar, Sep 10 2016


MATHEMATICA

Table[Prime[n + 1] + Prime[n]  Prime[n + 2], {n, 1, 30}][[;; ;; 2]] (* G. C. Greubel, Oct 08 2016 *)


PROG

(PARI) g(n) = forstep(x=1, n, 2, y=prime(x+1)+ prime(x) prime(x+2); print1(y", "))
(PARI) n=1; p=2; q=3; forprime(r=5, 1e3, if(n, print1(p+qr", ")); n=!n; p=q; q=r) \\ Charles R Greathouse IV, Oct 08 2016


CROSSREFS

Cf. A096379, A135274.
Sequence in context: A054858 A269704 A157971 * A304005 A304947 A013652
Adjacent sequences: A135272 A135273 A135274 * A135276 A135277 A135278


KEYWORD

nonn,easy


AUTHOR

Cino Hilliard, Dec 02 2007


EXTENSIONS

New name from Charles R Greathouse IV, Oct 08 2016


STATUS

approved



