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A279393 Bisection of primes congruent to 1 modulo 4 (A002144), depending on the corresponding sum of the A002972 and 2*A002973 entries being congruent to 1 modulo 4 or not. Here we give the second case. 2
5, 29, 37, 61, 73, 101, 113, 137, 173, 181, 193, 197, 241, 269, 277, 293, 349, 389, 409, 449, 509, 521, 541, 593, 613, 617, 653, 661, 673, 677, 701, 757, 761, 773, 821 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A279392 for details of this bisection of the primes of A002144. This sequence gives the part II of primes congruent 1 modulo 4.

LINKS

Table of n, a(n) for n=1..35.

FORMULA

A prime A002144(m) = A(m)^2 + B(m)^2 belongs to this sequence iff (-1)^((A(m)-1)/2 + B(m)/2) = -1, where A(m) = A002972(m) and B(m)/2 = A002973(m).

EXAMPLE

a(1) = 5 = A002144(1) and

A002972(1) = 1 and 2*A002973(1) = 2, hence 1 + 2 = 3 == 3 (mod 4), and 5 belongs to part II of this bisection.

CROSSREFS

Cf. A279392, A002144, A002972, A002973.

Sequence in context: A053244 A096696 A115279 * A182288 A087879 A091729

Adjacent sequences:  A279390 A279391 A279392 * A279394 A279395 A279396

KEYWORD

nonn,easy

AUTHOR

Wolfdieter Lang, Dec 11 2016

STATUS

approved

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Last modified May 20 13:24 EDT 2019. Contains 323422 sequences. (Running on oeis4.)