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A270541 a(n) = A001359(n) - A001359(n+1) - A001359(n+2) + A001359(n+3). 0
4, 6, 6, 6, 0, 12, -6, 0, 6, 0, 0, -24, 18, 6, 0, 0, 0, 24, 42, -24, -42, 48, 18, -30, -30, -6, 0, 126, -6, -144, 18, 18, 108, -12, -120, 0, 12, 48, 48, -12, -66, -36, 6, 96, 6, -78, -18, 90, 6, -72, 18, -24, 36, 60, -60, -30, 12, -6, 12, 6, -24, -30, 12, -12, 78, 18, -54, 0, 0, 138, 0, -102, -12, -42 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

6*k appears for the form of a(n) for n > 1.

What is the most repeated value of a(n)?

See A270535 for the position of 0's in this sequence.

LINKS

Table of n, a(n) for n=1..74.

FORMULA

a(n) = A053319(n+2) - A053319(n).

EXAMPLE

a(1) = 4 because a(1) = A001359(1) - A001359(2) - A001359(3) + A001359(4) = 3 - 5 - 11 + 17 = 4.

MATHEMATICA

s = Select[Prime@Range[10^6], PrimeQ[# + 2] &]; Table[s[[n]] - s[[n + 1]] - s[[n + 2]] + s[[n + 3]], {n, 74}] (* Michael De Vlieger, Mar 19 2016, after Robert G. Wilson v at A001359 *)

PROG

(PARI) t(n, p=3) = { while( p+2 < (p=nextprime( p+1 )) || n-->0, ); p-2}

a(n) = t(n) + t(n+3) - t(n+1) - t(n+2);

for(n=1, 200, print1(a(n), ", "));

CROSSREFS

Cf. A001359, A006512, A014574, A053319.

Sequence in context: A081261 A251738 A249022 * A046262 A147862 A029854

Adjacent sequences:  A270538 A270539 A270540 * A270542 A270543 A270544

KEYWORD

sign

AUTHOR

Altug Alkan, Mar 18 2016

STATUS

approved

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Last modified January 26 01:48 EST 2020. Contains 331270 sequences. (Running on oeis4.)