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A332449 a(n) = A005940(1+(3*A156552(n))). 4
1, 4, 9, 10, 25, 16, 49, 30, 21, 36, 121, 22, 169, 100, 81, 90, 289, 40, 361, 250, 225, 196, 529, 66, 55, 484, 105, 490, 841, 64, 961, 270, 441, 676, 625, 154, 1369, 1156, 1089, 750, 1681, 144, 1849, 1210, 39, 1444, 2209, 198, 91, 84, 1521, 1690, 2809, 120, 1225, 1470, 2601, 2116, 3481, 34, 3721, 3364, 1029, 810, 3025, 400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

Index entries for sequences computed from indices in prime factorization

FORMULA

a(n) = A005940(1+(3*A156552(n))).

a(p) = p^2 for all primes p.

a(u) = A332451(u) and A010052(a(u)) = 1 for all squarefree numbers (A005117).

a(A003961(n)) = A003961(a(n)) = A005940(1+(6*A156552(n))).

PROG

(PARI)

A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ From A005940

A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552

A332449(n) = A005940(1+(3*A156552(n)));

CROSSREFS

Cf. A000290, A003961, A005117 (positions of squares), A005940, A010052, A156552, A277010, A332450, A332451.

Cf. also A332223.

Sequence in context: A244863 A077584 A093896 * A191905 A113432 A129830

Adjacent sequences:  A332446 A332447 A332448 * A332450 A332451 A332452

KEYWORD

nonn

AUTHOR

Antti Karttunen, Feb 14 2020

STATUS

approved

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Last modified July 4 11:40 EDT 2020. Contains 335448 sequences. (Running on oeis4.)