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A345057
Distance to the next larger number k > n for which A011772(k) = A011772(n), or 0 if no such number exists.
3
0, 4, 0, 10, 5, 0, 14, 12, 3, 0, 44, 6, 13, 14, 0, 46, 17, 18, 38, 4, 0, 11, 230, 6, 25, 13, 90, 0, 29, 10, 62, 40, 33, 34, 70, 0, 37, 57, 39, 20, 41, 28, 86, 4, 0, 23, 1034, 40, 7, 25, 102, 78, 53, 9, 0, 28, 114, 145, 1652, 60, 61, 62, 63, 190, 260, 0, 134, 68, 23, 140, 284, 24, 73, 37, 25, 38, 154, 0
OFFSET
1,2
FORMULA
a(n) = A345056(n) - n.
PROG
(PARI)
A011772(n) = { if(n==1, return(1)); my(f=factor(if(n%2, n, 2*n)), step=vecmax(vector(#f~, i, f[i, 1]^f[i, 2]))); forstep(m=step, 2*n, step, if(m*(m-1)/2%n==0, return(m-1)); if(m*(m+1)/2%n==0, return(m))); }; \\ From A011772
A345057(n) = { my(x=A011772(n), y=binomial(x+1, 2)); for(i=1+n, y, if(A011772(i)==x, return(i-n))); (0); };
CROSSREFS
Cf. A000217 (positions of zeros), A002024, A011772, A066561, A345056, A345058.
Sequence in context: A331451 A164735 A293933 * A158976 A211243 A181626
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 07 2021
STATUS
approved