import java.io.PrintStream; import java.util.Scanner; public class Y444 { Scanner in = new Scanner(System.in); PrintStream out = new PrintStream(System.out); long MOD = 1000000007; Y444() throws Exception { int n = in.nextInt(); long c = in.nextLong(); int[] a = new int[n]; for (int i = 0; i < n; i++) { a[i] = in.nextInt(); } Matrix m = new Matrix(); for (int i = 0; i < n; i++) { m.a[i][i] = a[i]; m.a[i+n][i+n] = a[i]; for (int j = 0; j < i; j++) { m.a[i+n][j] = a[i]; m.a[i+n][j+n] = a[i]; } } Matrix power = m.pow(c - 1); long ans = 0; for (int i = 0; i < n; i++) { for (int j = 0; j < n; j++) { ans = (ans + a[j] * power.a[i+n][j]) % MOD; } } power=m.mul(m); out.println(ans); } public static void main(String argv[]) throws Exception { new Y444(); } class Matrix { long[][] a = new long[160][160]; Matrix mul(Matrix that) { Matrix ret = new Matrix(); for (int i = 0; i < a.length; i++) { for (int j = 0; j < a.length; j++) { for (int k = 0; k < a.length; k++) { ret.a[i][k] = (ret.a[i][k] + a[i][j] * that.a[j][k]); } if ((j & 7) == 7) { for (int k = 0; k < a.length; k++) { ret.a[i][k] %= MOD; } } } } return ret; } Matrix pow(long p) { Matrix ret = new Matrix(); Matrix x = this; for (int i = 0; i < a.length; i++) { ret.a[i][i] = 1; } while (p > 0) { if ((p & 1) == 1) { ret = x.mul(ret); } x = x.mul(x); p >>= 1; } return ret; } } }