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A249341 Positions of ones in A249337; positions of zeros in A249072. 5
1, 3, 7, 14, 21, 40, 46, 71, 81, 98, 122, 146, 194, 241, 258, 297, 323, 380, 401, 433, 482, 491, 533, 567, 633, 716, 761, 767, 808, 836, 879, 1068, 1105, 1210, 1216, 1370, 1415, 1469, 1515, 1541, 1606, 1684, 1707, 1854, 1872, 1906, 1936, 2117, 2277, 2294, 2305, 2344 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

FORMULA

For all n >= 2: a(n) = A249342(n) + 1.

PROG

(PARI)

allocatemem(234567890);

A049084(n) = if(isprime(n), primepi(n), 0); \\ This function from Charles R Greathouse IV

A056239(n) = { my(f); if(1==n, 0, f=factor(n); sum(i=1, #f~, f[i, 2] * A049084(f[i, 1]))); }

A249341_write_bfile(up_to_n) = { my(counts, n, k, a_k); counts = vector(min((2^24)-8, up_to_n^2)); n = 0; k = 0; a_k = 1; while(n < up_to_n, k++; if((1 == a_k), n++; write("b249341.txt", n, " ", k)); counts[1+A056239(a_k)]++; if(1 == k, a_k = 2, a_k = counts[1+A056239(a_k)])); };

A249341_write_bfile(10000);

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

(define A249341 (MATCHING-POS 1 1 (lambda (n) (= 1 (A249337 n)))))

(define A249341 (ZERO-POS 1 1 A249072))

CROSSREFS

After the initial term, one more than A249342.

Cf. A249337, A249339, A249072.

Sequence in context: A161210 A256059 A258434 * A310278 A154772 A156859

Adjacent sequences:  A249338 A249339 A249340 * A249342 A249343 A249344

KEYWORD

nonn

AUTHOR

Antti Karttunen, Oct 26 2014

STATUS

approved

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Last modified July 26 10:35 EDT 2021. Contains 346294 sequences. (Running on oeis4.)