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A302054
a(n) is the sum of prime divisors of A302033(n).
2
0, 2, 5, 3, 8, 10, 7, 5, 12, 14, 17, 15, 10, 12, 9, 7, 18, 20, 23, 21, 26, 28, 25, 23, 16, 18, 21, 19, 14, 16, 13, 11, 24, 26, 29, 27, 32, 34, 31, 29, 36, 38, 41, 39, 34, 36, 33, 31, 20, 22, 25, 23, 28, 30, 27, 25, 18, 20, 23, 21, 16, 18, 15, 13, 30, 32, 35, 33, 38, 40, 37, 35, 42, 44, 47, 45, 40, 42, 39, 37, 48, 50, 53, 51, 56, 58, 55, 53
OFFSET
0,2
LINKS
FORMULA
a(n) = A001414(A302033(n)) = A008472(A302033(n)).
MATHEMATICA
Array[Total@ Prime@ Flatten@ Position[#, 1] &@ Reverse@ IntegerDigits[BitXor[#, Floor[#/2]], 2] &, 88, 0] (* Michael De Vlieger, Apr 27 2018 *)
PROG
(PARI) first(n) = {my(pr = primes(1 + logint(n, 2)), ex = vector(#pr, i, 1), res = vector(n)); res[1] = 0; for(i = 1, n-1, v = valuation(i, 2); res[i + 1] = res[i] + pr[v++] * ex[v]; ex[v]*=-1); res}; \\ David A. Corneth, Apr 18 2018
(PARI)
A003188(n) = bitxor(n, n>>1);
A019565(n) = {my(j, v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ From A019565
A302054(n) = vecsum(factor(A019565(A003188(n)))[, 1]); \\ Antti Karttunen, Apr 24 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved