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A268963
Primes 4k+1 at the end of the maximal gaps in A084162.
3
5, 13, 29, 89, 137, 229, 509, 1549, 1861, 9601, 15733, 16829, 33289, 39709, 50741, 180949, 183289, 1562053, 1638053, 2244157, 4469141, 4874977, 7856713, 10087481, 12021353, 12214273, 18227081, 148364081, 292182557, 320262769, 468214457, 727335397, 869766761
OFFSET
0,1
COMMENTS
Subsequence of A002144.
A084161 lists the primes preceding the maximal gaps, and A084162 lists the corresponding gap sizes. See more comments there.
LINKS
FORMULA
a(n) = A084161(n) + A084162(n)
EXAMPLE
a(3) = 89: There are no primes p = 1 mod 4 between 73 and 89, this gap is the largest up to 89, the gap size is 16.
MATHEMATICA
Reap[Print[5]; Sow[5]; r = 0; p = 5; For[q = 7, q < 10^7, q = NextPrime[q], If[Mod[q, 4] == 3, Continue[]]; g = q - p; If[g > r, r = g; Print[q] Sow[q]]; p = q]][[2, 1]] (* Jean-François Alcover, Feb 20 2019, from PARI *)
PROG
(PARI) print1(5); r=0; p=5; forprime(q=7, 1e9, if(q%4==3, next); g=q-p; if(g>r, r=g; print1(", "q)); p=q)
CROSSREFS
KEYWORD
nonn
AUTHOR
Alexei Kourbatov, Feb 16 2016
STATUS
approved