A322991 - OEIS

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A322991

a(n) = A289272(2*A289271(n)).

1, 3, 4, 5, 7, 12, 8, 9, 11, 15, 13, 20, 16, 21, 28, 17, 19, 24, 23, 35, 36, 33, 25, 44, 27, 39, 29, 40, 31, 60, 32, 37, 52, 48, 56, 45, 41, 51, 68, 63, 43, 84, 47, 55, 77, 57, 49, 76, 53, 69, 92, 65, 59, 75, 91, 72, 100, 87, 61, 140, 64, 93, 88, 67, 112, 132, 71, 80, 108, 105, 73, 99, 79, 96, 116, 85, 104, 156, 81, 119, 83, 111, 89

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16384

FORMULA

a(n) = A289272(2*A289271(n)).

PROG

(PARI)

A289271(n) = { my(v=0, i=0, x=1); for(d=2, oo, if(n==1, return(v)); if(1==gcd(x, d)&&1==omega(d), if(!(n%d)&&1==gcd(d, n/d), v += 2^i; n /= d; x *= d); i++)); }; \\ After Rémy Sigrist's program for A289271.

A289272(n) = { my(m=1, pp=1); while(n>0, pp++; while(!isprimepower(pp)||(gcd(pp, m)>1), pp++); if(n%2, m *= pp); n >>=1); (m); };

A322991(n) = A289272(2*A289271(n));

CROSSREFS

Permutation of A042965 (apart from zero).

Cf. A289271, A289272, A322990, A322992.

Cf. also A003963, A300841.

Sequence in context: A046413 A353969 A285224 * A120635 A300841 A023713

Adjacent sequences: A322988 A322989 A322990 * A322992 A322993 A322994

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jan 01 2019

STATUS

approved