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A270431 Numbers n such that A048673(n) and A064216(n) are of opposite parity. 6
6, 7, 11, 14, 15, 18, 19, 21, 22, 23, 24, 28, 35, 38, 43, 44, 45, 46, 47, 51, 54, 55, 56, 57, 59, 60, 61, 63, 66, 67, 70, 71, 72, 73, 76, 78, 79, 83, 84, 86, 87, 88, 89, 91, 92, 94, 95, 96, 103, 107, 110, 112, 115, 118, 119, 122, 123, 127, 129, 131, 134, 135, 138, 140, 142, 143, 146, 150, 152, 153, 157, 158, 159, 162 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See comments in A270434.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..17000

FORMULA

Other identities. For all n >= 1:

A270433(a(n)) = n.

MATHEMATICA

f[n_] := (Times @@ Power[If[# == 1, 1, NextPrime@ #] & /@ First@ #, Last@ #] + 1)/2 &@ Transpose@ FactorInteger@ n; g[n_] := Times @@ Power[If[# == 1, 1, NextPrime[#, -1]] & /@ First@ #, Last@ #] &@ Transpose@ FactorInteger[2 n - 1]; Select[Range@ 162, Xor[EvenQ@ f@ #, EvenQ@ g@ #] &] (* Michael De Vlieger, Mar 17 2016 *)

PROG

(Scheme, with Antti Karttunen's IntSeq-library)

(define A270431 (NONZERO-POS 1 1 (lambda (n) (- (A000035 (A048673 n)) (A000035 (A064216 n))))))

CROSSREFS

Complement: A270430.

Left inverse: A270433.

Cf. A000035, A048673, A064216, A270434.

Cf. also A269861.

Sequence in context: A081715 A054504 A190612 * A315832 A224856 A182156

Adjacent sequences:  A270428 A270429 A270430 * A270432 A270433 A270434

KEYWORD

nonn

AUTHOR

Antti Karttunen, Mar 17 2016

STATUS

approved

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Last modified November 14 09:51 EST 2019. Contains 329111 sequences. (Running on oeis4.)