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A233420 Minimal number of c-squares (A020330) and/or 1's which add to n. 3
1, 2, 1, 2, 3, 2, 3, 4, 3, 1, 2, 3, 2, 3, 1, 2, 3, 2, 3, 2, 3, 4, 3, 4, 2, 3, 4, 3, 4, 2, 3, 4, 3, 4, 3, 1, 2, 3, 2, 3, 4, 3, 4, 5, 1, 2, 3, 2, 3, 4, 2, 3, 4, 1, 2, 3, 2, 3, 4, 2, 3, 4, 1, 2, 3, 2, 3, 4, 2, 3, 4, 2, 2, 3, 3, 3, 4, 2, 3, 4, 2, 3, 3, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Conjecture: the sequence is bounded by a constant.

LINKS

Table of n, a(n) for n=1..84.

EXAMPLE

For n=33, we have 33=15+15+3. Since 33 is not in union of {1} and c-squares and is not a sum of two such numbers, then a(33)=3.

PROG

(PARI) v=vector(10^5, n, n+n<<#binary(n)); \\ choose large enough that v[#v] > n for a(n) below.

a(n)=if(setsearch(v, n), return(1)); if(n<3, return(n)); my(where=setsearch(v, n+1, 1), t=n); if(!where, where=setsearch(v, n, 1)); forstep(i=where-1, 1, -1, t=min(w(n-v[i]), t); if(t==1, return(2))); t+1 \\ Charles R Greathouse IV, Dec 10 2013

CROSSREFS

Cf. A020330, A233312.

Sequence in context: A053735 A033667 A033923 * A220098 A246017 A116939

Adjacent sequences:  A233417 A233418 A233419 * A233421 A233422 A233423

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Dec 09 2013

STATUS

approved

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Last modified July 16 23:49 EDT 2019. Contains 325092 sequences. (Running on oeis4.)