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 A082266 In the array shown below the n-th row contains all the palindromes that use digits > 0 and have a digit sum of n. The sequence contains the array read by rows. 4
 1, 2, 11, 3, 111, 4, 22, 121, 1111, 5, 131, 212, 11111, 6, 33, 141, 222, 1221, 2112, 11211, 111111, 7, 151, 232, 313, 11311, 12121, 21112, 1111111, 8, 44, 161, 242, 323, 1331, 2222, 3113, 11411, 12221, 21212, 112211, 121121, 211112, 1112111, 11111111 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA For formulas see A082267. EXAMPLE In the following array the n-th row contains all the palindromes that use digits > 0 and have a digit sum of n. 1 2 11 3 111 4 22 121 1111 5 131 212 11111 6 33 141 222 1221 2112 111111 ... The sequence contains the array read by rows. MAPLE isPali := proc(perm) local i ; for i from 1 to nops(perm)/2 do if op(i, perm) <> op(-i, perm) then RETURN(false) ; fi ; od ; RETURN(true) ; end: isSingDig := proc(perm) local i ; for i from 1 to nops(perm) do if op(i, perm)>9 then RETURN(false) ; fi ; od ; RETURN(true) ; end: A082266 := proc(n) local arow, npart, pindx, part, perm, i, cand, j, pali ; arow := [] ; npart := combinat[partition](n) ; for pindx from 1 to nops(npart) do part := op(pindx, npart) ; perm := combinat[permute](part) ; for i from 1 to nops(perm) do cand := op(i, perm) ; if isSingDig(cand) and isPali(cand) then pali := add( op(j, cand)*10^(j-1), j=1..nops(cand) ) ; arow := [op(arow), pali] ; fi ; od ; od ; RETURN(sort(arow)) ; end: for n from 1 to 10 do arow := A082266(n) : for i from 1 to nops(arow) do printf("%d, ", op(i, arow)) ; od : od : # R. J. Mathar, Mar 07 2007 CROSSREFS Cf. A082264, A082265, A082267. Sequence in context: A339616 A073331 A109858 * A070840 A235460 A082264 Adjacent sequences:  A082263 A082264 A082265 * A082267 A082268 A082269 KEYWORD base,nonn,tabf AUTHOR Amarnath Murthy, Apr 12 2003 EXTENSIONS Corrected and extended by R. J. Mathar, Mar 07 2007 STATUS approved

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Last modified September 22 07:37 EDT 2021. Contains 347605 sequences. (Running on oeis4.)